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Victron Energy Cables: Explained!
VE.Bus, VE.CAN, VE.Direct, Wakespeed, SeeLevel and more! We hope you’re sitting down to read this blog, because this post covers the super exciting topic of communication cables! Victron Energy currently offers more than 20 different communication cables for their electrical devices, and that doesn’t include even more “cables” that Victron chooses to call “sensors”. But don’t worry, we’re not here to bore you with long descriptions of every single cable available. We’re here to bore you with just a handful of the popular cables needed for camper van electrical systems. Cable-shaming aside, the numerous Victron electrical devices, protocols, and cables that are required for your system can be a confusing topic. And you need to have the correct cables for your system to work properly. So let’s dive in. All of these cables (and more!) are laid out in our camper van electrical system blog posts and corresponding free example wiring diagrams. If those posts plus this blog still doesn’t make it clear, we are always happy to help so please contact us. This guide focuses on Victron Energy system cables – the data and communication cables that let Victron components share information and work together (VE.Bus, VE.CAN, VE.Direct, and related adapters). This guide does not cover battery or inverter power cable sizing (which requires a separate fuse and wire-size approach). Table of Contents Here’s a list of all of the super exciting cables covered in this blog. Victron Cable Top 3 VE.Bus / VE.CAN VE.Direct Battery Extension Other Useful Cables RJ10 Temperature sensor Wakespeed to Victron crossover RV-C to VE.CAN adapter Keep reading for all the gory cable details. But check out this at-a-glance table to whet your cable appetite. Cable type Device it connects to Typical cable quantity VE.Bus Multiplus 1 VE.CAN Lynx Shunt Lynx BMS 1 VE.Direct Orion XS MPPT Charge Controller 1 per device if you have a Cerbo Battery Extension Lynx BMS 1 RJ10 Lynx Distributor 1 (included with Lynx Distributor) Temperature sensor Multiplus 1 (included with Multiplus) Wakespeed to Victron crossover Wakespeed WS500 & Pro 1 RV-C to VE.CAN adapter SeeLevel panel 1 Victron Cable Top 3 Here are the three most-needed cables for Victron equipment in your rig. VE.Bus / VE.CAN Cables are Ethernet-style cables used by higher-power and higher-speed Victron devices such as Multiplus inverter/chargers, Lynx Shunts, and Lynx Smart BMS. Cerbo GX communication centers connect to those high power/speed devices and have both VE.Bus ports and VE.CAN ports, which are connections using different protocols for different devices that confusingly but conveniently happen to share the same cable type. VE.Direct Cables are proprietary cables used by lower-power and lower-cost Victron devices such as Orion XS DC-DC chargers and SmartSolar MPPT Charge Controllers. Typically, VE.Direct cables are used to connect these devices to a Cerbo GX. M8 (Circular) Battery Extension Cables are used to connect Lithium Smart & NG batteries communications to an external Smart BMS. More details about these cables are covered below. And don’t you worry, we’ll touch on a few more important cables too! Most Victron devices have only one type of communication, therefore you only need to understand one cable per device. The main exception is the Cerbo GX communication center, which supports almost all of the communication & cable types in order to function as a center-of-communications. If you have a Cerbo in your system, which is highly recommended, then we suggest auditing your other Victron devices and temporarily ignoring the Cerbo itself. After all, all of those other devices will be connected to the Cerbo, and let’s not further confuse things by double-counting cables. Lastly, if you don’t have a Cerbo GX, then you probably just need one VE.Bus / VE.CAN cable for your Multiplus inverter/charger. Keep reading for funsies, but that may be all you need to know! VE.Bus / VE.CAN Cables Most camper van electrical systems have a Multiplus inverter/charger, and Multiplus devices are VE.Bus products. In addition to Multiplus devices, some standalone BMS devices use VE.Bus. VE.Bus runs the Victron MK2/MK3 protocol, which is a fancy way of saying Victron uses a proprietary, serial communication protocol for their Multiplus & other VE.Bus products. VE.CAN devices typically used in camper vans include Lynx Shunts, Lynx Smart BMS, and certain higher-powered MPPT Charge Controllers. VE.CAN runs a CAN protocol that supports a mix of Victron proprietary and 3rd party “structures”. We’ll talk about some of that 3rd party support a little bit later in Other Useful Cables. Both the VE.Bus and VE.CAN communication ports use the same cable. We offer several of the most popular lengths of VE.Bus / VE.CAN cables in our store. How many VE.Bus / VE.CAN cables do you need? If you do not have a Cerbo in your system, the answer is likely one, which would be the number of Multiplus inverter/charger devices in your rig. You’ll still want one cable to configure and update firmware in your Multiplus even if you don’t use a Cerbo. You may also want to understand Victron dongles in that case. If you do have a Cerbo, then prepare for math. This is not so tough math where the answer is typically one or two. Add up the number of Multiplus inverter/chargers, then add one more if you have a Lynx Shunt or BMS. Even if you have a ton of solar and use a MPPT with VE.CAN, those devices also have VE.Direct ports; you must use one cable or the other (not both together) on those MPPTs, and we find it easiest to stick with VE.Direct for all MPPT Charge Controllers. Our suggestion is to buy a longer cable than you think is necessary. The cost difference between the common cable lengths is negligible. It’s best to coil up any excess cable when you’re dressing your completed system. Don’t short yourself (literally!) and make maintenance or future changes difficult. You can use off-the-shelf Ethernet cables with couplers to extend these cables, but if you do please use high quality CAT6e cables. Your critical Multiplus & BMS information relies on good quality communication, and that means you need good quality cables. Terminators are mini-cables, and they can be confusing too. Those blue things that come in your Cerbo box that look like Ethernet connectors with no wire? That’s the terminators we’re talking about. What do you do with the terminators? Do not use terminators on the VE.Bus. Any unused VE.Bus ports on your Multiplus or on your Cerbo can remain open & unused. Unused VE.CAN ports require terminators. Any unused CAN port on your Lynx Shunt or Lynx Smart BMS needs a terminator. Cerbo GX devices have two “sets” of CAN ports, one labeled VE.CAN and one labeled BMS-CAN. Any unused port in a “set” that is used needs a terminator. Hopefully a picture is worth a thousand words, and the next section makes that clear. BONUS Cerbo GX VE.Bus and VE.CAN Connections: Explained! We know that some of you are drifting off already. Stay frosty! If you’re going to learn about cables, it’s probably pretty important to plug the cables into the right places too. Don’t forget that all of these cables are nicely laid out in our example wiring diagrams too. This blog is focused on the popular communication cables for Victron equipment. Those popular cable locations on the Cerbo are highlighted below. When looking at the front face of the Cerbo, there are six Ethernet-like ports in a row along the back of the device (closest to the mounting surface); these six ports are the VE.Bus and VE.CAN ports (right to left). The purple box shows the two VE.Bus ports. Typically you’ll use one of the two ports for your Multiplus inverter/charger connection, and the remaining one will be empty. The blue boxes show the two “sets” of two CAN ports, titled VE.CAN and BMS-CAN. These are two separate CAN buses that can be configured to use different protocols and speeds. We recommend that your Lynx Shunt or Lynx Smart BMS (and maybe your Wakespeed regulator as part of your secondary alternator system) use the VE.CAN ports. If you have additional CAN devices such as batteries with Victron communications or a SeeLevel Tank Monitoring Kit, those can use the BMS-CAN port. Remember that if you use only one of the two ports in a “set”, the remaining port in that “set” needs a terminator. If you don’t use the VE.CAN ports or the BMS-CAN ports at all, then no worries a terminator isn’t critical. Above the VE.CAN and VE.Bus ports (closest to the pretty blue front cover and away from the mounting surface), there is another row with a bunch of different port types. The red box shows the Cerbo Ethernet port. As in not Ethernet-like but really Ethernet for a connection to a Starlink or additional router. Many customers confuse this port on the top row for a VE.Bus connection. The green boxes show the VE.Direct ports, and those are important for the next type of popular communication cables. VE.Direct Cables Victron devices with VE.Direct communication include the newer Orion XS DC-DC chargers (XS 50 and XS 1400; unfortunately none of the previous generation Smart DC-DC chargers support VE.Direct) and almost every BlueSolar and SmartSolar MPPT Charge Controller (except some very old and low-power versions not typical in camper vans at this point). If you have upgraded from a BMV-712 Smart Battery Monitor to add a Cerbo, you will also benefit from using the VE.Direct port on the monitor. VE.Direct is a proprietary serial interface that uses Victron-specific VE.Direct cables available in many lengths through our store. How many VE.Direct cables do you need? If you do not have a Cerbo in your system, you do not need any VE.Direct cables. If you do have a Cerbo, then prepare for some more math. But this is still fingers-on-one-hand kind of math, so don’t worry. Add up the number of Orion XS DC-DC Chargers (typically one or two), then add the number of MPPT Charge Controllers (typically one or two), and then add one more if you have a BMV-712. If you counted past three, read the next paragraph. You’ll need from zero to three VE.Direct cables in a system. Keep in mind that the Cerbo GX provides three VE.Direct ports (those green ones in the Cerbo pic above). If you have a robust system with more than three VE.Direct devices, you will need to expand your empire by using a VE.Direct to USB Interface Cable for the 4th (and even 5th?) VE.Direct device. The interface cable includes the USB end and the VE.Direct end, so you do not have to add yet another VE.Direct cable. Those additional VE.Direct devices would plug into USB ports on the Cerbo instead. As in the VE.Bus / VE.CAN cables, our suggestion is to buy a longer VE.Direct cable than you think is necessary. It’s not practical to extend VE.Direct cables. It’s best to buy long and coil up any excess cable when you’re dressing your completed system. M8 (Circular) Battery Extension Cables M8 Battery Extension Cables can be used to extend the BMS communication cable pigtails that come attached to Victron Lithium Smart and NG batteries. The pigtails on the batteries are 20 in long, so in most practical camper van electronic system layouts one M8 Battery Extension Cable (pair) is required to connect your battery bank to your BMS. M8 Battery Extension Cables come as a pair, and our store has several Battery Extension Cable length options to choose from. How many M8 Battery Extension Cables do you need? If you do not have a Victron ‘external BMS’ system using Lithium Smart or NG batteries, then you do not need any M8 Battery Extension Cables. If you do have a Victron ‘external BMS’ system using Lithium Smart or NG batteries, then you likely need one M8 Battery Extension Cable (pair). In keeping with our cable length theme, make sure that you select a long enough cable to allow for Manhattan routing and room for maintenance. A little extra coiled up cable is a wise choice. Other Useful Cables Here are four more cables for Victron systems worthy of a quick discussion. 1) The RJ10 cable Yes, Victron calls it the “RJ10 cable” and nothing more, so we’re sticking with that. Every Lynx Distributor comes with a 15 inch, 4-pin cable that is essentially an old telephone cord. (Let’s just assume you’re old enough to understand that reference! If not, ignore.) The RJ10 cable allows a Lynx Shunt or Smart or NG BMS to power the Distributor LEDs and report blown fuse detection. If you don’t have a Lynx Shunt or Smart BMS, then you do not need to use that RJ10 cable. If you really want to see those Lynx Distributor LEDs on without a Lynx Shunt or BMS, then check out the Turning On The LED Lights On The Lynx Distributor hack at the end of this blog. 2) Temperature sensor for Multiplus or Cerbo GX Your Multiplus inverter/charger comes with a temperature sensor (aka cable) that is typically used to measure battery temperature by attaching the ring lug to the negative post. This cable can also be used as an input to a Cerbo GX. If you have Victron Lithium Smart or NG batteries, or if you’re using batteries with Victron communications in conjunction with DVCC, then you do not need to use the temperature sensor. For systems with internal BMS batteries without communication, using the temperature sensor with your Multiplus is a wise approach to prevent damaging your batteries in extreme temperatures. If you misplaced (lost!) the cable that was included with your Multiplus, it is also available in our store. 3) Wakespeed to Victron Crossover Cable If you’re using a secondary alternator system for massive charging power, you’ll likely want to include a Wakespeed to Victron Crossover Cable. This cable supports the CAN communication between your BMS (via the Cerbo) and a 3rd party device, the Wakespeed regulator. Don’t forget that the blue end of the crossover cable plugs into your Victron equipment, and the black end of the crossover plugs into your Wakespeed regulator. A black terminator is also included, and that plugs into the unused CAN port on your Wakespeed. The Wakespeed to Victron Crossover Cable is 4’ long, and the cable can be extended with a high-quality Ethernet cable and coupler. 4) RV-C to VE.CAN Adapter for SeeLevel This SeeLevel Tank Monitoring Kit is a nice addition to systems with a Cerbo GX. This 3rd party kit is actually a nice addition to any system, but you won’t worry about the RV-C to VE.CAN Adapter for SeeLevel cable unless you have a Cerbo! This cable plugs into the back of a Garnet SeeLevel 709-N2K-NLP panel and allows the RV-C protocol to plug into one of the Cerbo CAN ports (either VE.CAN or BMS-CAN, as you’ll need to change the protocol and speed as part of configuration). RV-C uses CAN, so yes you need to use terminators. The terminator for the panel is included as part of the adapter cable, but don’t forget to use the blue terminator in any unused CAN port at your Cerbo. The RV-C to VE.CAN Adapter for SeeLevel is 6’ long, and the cable can be extended with a high-quality Ethernet cable and coupler. Wrap Up - Cable Selection Guide At A Glance Whether you program your Multiplus with a dongle or through your Cerbo GX, you’ll still need a VE.Bus cable. Your device What to buy Have a Multiplus? Add one VE.CAN / VE.Bus cable If you have a Cerbo GX, and we highly recommend that you do, follow this guide: Your device What to buy Have a Lynx Shunt or Lynx BMS? Add one VE.CAN / VE.Bus cable Have a Orion XS 50 or XS 1400 DC-DC Charger? Add one VE.Direct cable for each charger Have a MPPT Charge Controller? Add one VE.Direct cable for each controller Have a Wakespeed WS500? Add one Wakespeed to Victron crossover cable Have a SeeLevel Tank Monitoring Kit? Add one RV-C to VE.CAN adapter But it’s okay if you don’t have a Cerbo. You probably do not require any more communication cables. Frequently Asked Questions 1. How many VE.Direct devices can a Cerbo support? The Cerbo GX allows up to three VE.Direct cables to be plugged in. For additional VE.Direct devices, use a VE.Direct to USB Interface Cable instead. Those additional VE.Direct devices will use USB ports on the Cerbo. 2. Do I need terminators for VE.CAN? Plug terminators into unused CAN ports. Use blue terminators on unused Victron VE.CAN ports. Use black terminators on unused Wakespeed CAN ports. Do not use terminators on unused VE.Bus ports. 3. What is the difference between VE.Bus and VE.CAN? VE.Bus and VE.CAN are both communications protocols, but the protocols use different technologies and are supported by different types of products. Multiplus inverter/chargers are VE.Bus products. Lynx Shunts and BMS use VE.CAN. Both VE.Bus and VE.CAN use the same cables. 4. What is the difference between VE.Bus and VE.Direct? VE.Bus and VE.Direct are both communication protocols, however they use different cables and work on different devices. VE.Bus units are typically high-power devices like Multiplus inverter/chargers. VE.Direct units are typically lower power devices such as DC-DC chargers and MPPT Charge Controllers. 5. Can I extend Victron cables? VE.Bus / VE.CAN cables, a Wakespeed to Victron Crossover Cable, and a RV-C to VE.CAN Adapter for SeeLevel can all be extended using high quality Ethernet cables and couplers. It is not practical to extend VE.Direct cables - buy a longer cable. Additional Resources Victron Cables product information Victron Data Communication white pape Secondary Alternator Example Power System Accurate Tank Monitoring with a Cerbo GX and SeeLeve Free example wiring diagrams
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Victron Energy Dongles: Explained!
Interface MK3 to USB, VE.Bus Smart, and VE.Direct Bluetooth Smart What is a dongle and when do I need one? This post explains Victron Energy’s confusing accessories for configuring and monitoring Victron systems. First, let’s get this out of the way. A dongle is a small device able to be connected to and used with a computer. Sometimes Victron calls it a dongle. Sometimes Victron calls it an interface. We dunno, but we’ll call it a dongle if you call us asking for more info on our Victron products. Types of Dongles Victron offers several dongles for different purposes and products. If you need to configure settings, update firmware, or remotely monitor your Victron device with VictronConnect, keep reading! As of this posting (early 2026), our store has three types of Victron Energy dongles available. Most camper van electrical systems are interested in the first two of these dongles below, while some customers upgrading older non-Bluetooth devices may be considering the third dongle. Let’s break them down. An Interface MK3 to USB (we’ll call it a MK3-USB dongle!) is used to configure settings and update firmware for VE.Bus products. VE.Bus products are Multiplus inverter/chargers, standalone BMS, and some inverters. There are two MK3-USB dongle options, with the only difference between the two being a USB-A connector (the O.G. rectangular USB connection) versus a USB-C connector (the newer, slimmer port as found on phones, tablets, etc.). A VE.Bus Smart Dongle is used to monitor and operate VE.Bus products via Bluetooth. “Operate” means changing the input current limit as well as switching between Off, On and Charger-only modes on an inverter/charger. A VE.Direct Bluetooth Smart Dongle adds a Bluetooth interface to monitor devices such as the BMV-70x series battery monitors (not the newer BMV-712 with integrated Bluetooth), Phoenix Inverters with VE.Direct port, and MPPT Solar Charge Controllers without Bluetooth. Don’t confuse VE.Bus devices with VE.Direct devices. VE.Bus units are typically high-power devices like Multiplus inverter/chargers, and these devices use an “Ethernet” VE.Bus cable. VE.Direct units are typically lower power devices such as DC-DC chargers and MPPT Charge Controllers, and these devices use a proprietary VE.Direct cable. Each of those device types needs a different dongle. What’s up with all these Victron protocols and cables? Check out our Victron Energy Cables: Explained! blog. When do I need a MK3-USB dongle? A MK3-USB dongle (again, formally titled an Interface MK3 to USB by Victron) can be used to configure settings and update firmware on your Multiplus via the VictronConnect app. Victron still ships Multiplus products configured for AGM batteries, so most customers need to configure their inverter/chargers for lithium-ion batteries and adjust their settings as explained here. However, if your system has a Cerbo GX command center, you can perform all of the configuration steps and firmware updates using the VRM without needing a separate MK3-USB dongle. You have two options for configuring your Multiplus settings and updating firmware 1) with a Victron Cerbo through the VRM or 2) using a laptop/phone* directly to a MK3-USB dongle. You MUST pick one of these options. Since you’ll need at least one dongle to configure and update your Multiplus, and maybe you want the ability to control your Multiplus remotely with a second dongle (see next section below), we highly recommend considering a Cerbo GX instead of worrying about dongles at all. You get more features, consolidated configuration & operation, plus the ability for remote troubleshooting & diagnostics for just a little more investment. Bonus tip: while we think the Cerbo pairs perfectly with a touch screen, you can use the Cerbo through VRM and/or Bluetooth without a touch screen if you choose. If you choose to use a MK3-USB dongle for configuring your Multiplus and you do have a Cerbo in your system, don’t forget that those VE.Bus connections should be mutually exclusive. Connect the VE.Bus cable to your dongle initially, then disconnect the dongle and make the connection from the Cerbo to the Multiplus. Put your dongle in your maintenance area, as you may need it for future firmware updates. If you need a MK3-USB dongle, your only decision is to pick between USB-A (top) and USB-C (bottom) connectors. Aside from the connector, both dongles perform the same functions. Generally speaking, laptops using VictronConnect and/or VEConfigure software trend towards USB-A ports, and newer phones & tablets using VictronConnect are using USB-C ports. Lastly, if you’re a power user or in a big rig with multiple Multiplus devices in split-phase or parallel configurations, then you will need a MK3-USB dongle for proper configuration of the inverter/chargers. When do I need a VE.Bus Smart Dongle? A VE.Bus Smart Dongle adds Bluetooth connectivity to a Multiplus for monitoring and control only. You can not configure settings or perform firmware updates using a VE.Bus Smart Dongle. That’s why we talked about the MK3-USB dongle above! Via the VictronConnect app, the VE.Bus Smart Dongle allows you to readily see an inverter/charger’s key stats as well as warnings or alarms. The VE.Bus Smart Dongle also allows you to control the input current limit and mode (Off, On aka Inverter/Charger, and Charger-only). These operator controls provide a way to replace a Digital Multi Control Panel with Bluetooth connectivity. The VE.Bus Smart Dongle is an optional device that can add Multiplus monitoring & operation in a system without a Cerbo. The VE.Bus Smart Dongle connects to a device with a VE.Bus cable that is not included. When do I need a VE.Direct Smart Dongle? The VE.Direct Bluetooth Smart Dongle adds Bluetooth connectivity to VE.Direct devices for monitoring only. Don’t confuse the VE.Bus Smart Dongle for VE.Bus devices such as a Multiplus with this one, which is for VE.Direct devices such as BMV-70x series battery monitors, Phoenix Inverters with VE.Direct port, and BlueSolar MPPT Solar Charge Controllers without Bluetooth. If you have a SmartSolar MPPT Solar Charge Controller like the ones in our store, those pretty blue boxes already have Bluetooth capability without the need for this extra dongle. Via the VictronConnect app, the VE.Direct Smart Dongle allows you to readily see a device’s key stats as well as warnings or alarms. The VE.Direct Smart Dongle is an optional device that can add remote monitoring to VE.Direct devices that lack Bluetooth connectivity. The VE.Direct Smart Dongle has an integral cable that plugs directly into a single device with a VE.Direct port. Wrap Up - Quick Selection Guide Here it is in a nutshell: Your device & goal What to buy Have a Cerbo GX? You likely don’t need a dongle Configuring or updating a MultiPlus MK3-USB and a VE.Bus cable Bluetooth monitoring for MultiPlus VE.Bus Smart Dongle and a VE.Bus cable Bluetooth for older VE.Direct devices VE.Direct Smart Dongle Remember to “match the port”. Use a VE.Bus dongle for Multiplus. Use a VE.Direct dongle for most other devices with a VE.Direct port. Frequently Asked Questions 1. What software do I need to connect to a dongle? All Victron dongles require the VictronConnect app. * Note that Apple iPhone/iPad doesn't support USB OTG, so Bluetooth connections work fine from an iDevice but the MK3-USB dongle requires either a Windows/Mac laptop or an Android device. 2. VictronConnect won’t connect - what should I try first? Troubleshoot common VictronConnect and Bluetooth issues in three steps. Make sure the Bluetooth is on in your phone’s system menu Move your phone very close to the device If you’re still not connecting, then 1) close VictronConnect 2) remove the device pairing from you phone’s Bluetooth system menu 3) open VictronConnect and pair with the device from within the VictronConnect Local screen. 3. Do I need to configure my Victron electrical system? Yes. Factory defaults are not correct for lithium-ion batteries and most camper van electrical systems. You need to configure the settings in all of your electrical devices, and you need the capability to update firmware when necessary. 4. How do I choose between a USB-A dongle and a USB-C dongle? The only difference between the USB-A dongle and the USB-C dongle is the connection to your laptop or phone. Select USB-A for the traditional USB connector, or select USB-C for more modern devices with only USB-C ports. There are also adapters available to readily switch between the two physical connectors. 5. What is the difference between VE.Bus and VE.Direct? VE.Bus and VE.Direct are both communication protocols, however they use different cables and work on different devices. VE.Bus units are typically high-power devices like Multiplus inverter/chargers. VE.Direct units are typically lower power devices such as DC-DC chargers and MPPT Charge Controllers. Additional Resources Victron Accessories product information Configuring a Multiplus using a MK3-USB dongle Troubleshooting VictronConnect
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How To Configure Your Victron Electrical System Components Using VRM
The Victron ecosystem has very useful monitoring and configuration capabilities when a Cerbo is installed as part of your camper van electrical system. One of the benefits of purchasing a Victron system bundle from Vanlife Outfitters is your access to our expert tech support team. Victron's Remote Monitoring (VRM) allows us to see what your system is doing, and help you remotely troubleshoot or adjust device configuration settings. The Cerbo can connect to Wi-Fi and the internet, allowing remote access to view system data and edit configuration settings of connected devices. Settings and firmware updates can be managed for the Cerbo itself, most Victron inverters and battery chargers, all SmartSolar MPPT solar charge controllers and Victron Orion XS DC-DC controllers with VE.direct, all remotely. This gives an extra way to do device configuration & updates from one location, vs. the typical methods of bluetooth with the Victron Connect app, or an MK3-USB cable for Multiplus inverters. That one location is Victron’s remote monitoring portal, VRM, and it can be accessed from anywhere through the cloud. Since your camper van is typically mobile, it’s great that it can be accessible remotely. Requirements: Good Wi-Fi connection with the Cerbo to the internet. A Windows OS machine (or virtual machine) with Victron’s VEConfigure installed. TIP: You don’t need to have always-on internet in your rig. Many customers use the VRM at home or temporarily using a hotspot if needed. Your touch screen and system will continue to work with or without internet. The Victron system will store data when not connected then upload it when you’re back home. The Cerbo’s internal antenna is not meant for long range connections, and, it’s inside your metal box van...so a strong Wi-Fi signal may be necessary. The wireless network must be a simple SSID and password login. The Cerbo can not connect to networks where a captive login webpage requires other interaction. We highly recommend that you set up VRM following the steps below! Assuming your Cerbo is working and connected with the rest of your system, follow these steps to connect and set up VRM, and invite us to view your system. If you still need to turn on the Cerbo in the first place, and set it up for your camper van electrical system, here is a more detailed complete blog post. https://www.vanlifeoutfitters.com/configuring-a-victron-cerbo-gx-and-connecting-with-vrm Either way, now you should be able to view your system on VRM. On a web browser, go to https://vrm.victronenergy.com and click on Installations, and it should look something like this: ('Device List' and 'Remote Console' are highlighted for next steps.) Very good, you have VRM set up! Now we can talk about using it for remote configuration! Exciting! Using the VRM remotely from a web browser, or the Victron VRM app for Apple or Android, you can see data or change settings as if you were using the touch screen display locally. You can do this from far, far away, or you can use VRM in your camper van without needing the special MK3-USB cable that you forgot where you stashed. When VRM is connected to your system, the Remote Console view is the same as what you see locally on the touch screen. (Click 'Remote Console' from VRM Dashboard.) From this screen, you can view Notifications and Settings. (Click anywhere on the screen to show the lower toolbar icons, just like on the touchscreen in your van.) VRM Device list view, and firmware updates: (From the VRM dashboard, click 'Device List'.) The device list shows all connected devices. Click the ‘+’ at the right side to see info about each device (serial numbers, current firmware version, etc). The Firmware Update button takes you to a new screen with the current firmware and the latest available version for each device. The latest f/w should be used for starting up new systems, and sometimes firmware updates can solve certain problems on older systems. If your system is working fine and there’s no new feature that you want, then it is fine to stay with your current firmware version. This is the easiest way to update firmware for multiple devices. For a new system, use the latest firmware for every device. Read the messages carefully when updating firmware. Remote configuration of devices via VRM – Multiplus inverters: For Multiplus settings, a configuration file can be downloaded, edited locally with VEConfigure (windows OS only), then re-uploaded to the Multiplus. Using VRM, this can be done without a special MK3-USB cable, which is the other typical way to configure a Multiplus (locally, MK3-USB cable between the inverter and laptop). (Choose Device list, Remote VEConfigure.) A pulldown list shows your Multiplus in case there are more than one, then choose Download. The .rvsc configuration file with the current inverter settings will be downloaded to your local machine. You might make a copy of the original file at this point, because VEConfigure will overwrite it with your changes. Pre-step: install VEConfiguration tools from Victron: https://www.victronenergy.com/support-and-downloads/software Once VEConfigure is installed, you should be able to double click the downloaded .rvsc file and VEConfigure will be launched, showing the General settings tab. You can also open VEConfigure manually on your windows machine and select the file. This would be similar to plugging directly into the inverter with the MK3-USB cable. The windows VEConfigure program is used to view and modify the settings. (If you’re a Mac or Linux user, all this does work fine from windows running on a virtual machine, like VirtualBox). If you launched VEConfigure manually, Click ‘Port selection’, ‘Fake target from file’ and choose the previously downloaded .rvsc file. Then you should see the General settings tab as shown above. The existing settings from your config file populate in the various tabs of VEConfigure: General tab settings shown here are fine: 60Hz for North America, the default 30a shore power inlet current limit you may want to set at 11amps to avoid tripping 15a outlet circuits with continuous charging load. Don’t enable the battery monitor unless there is no other shunt in the system. Typically, you want the shunt to be the primary measurement of battery SOC, not the multiplus. Default values on the Grid tab should also be fine: (Grid code: none, accept wide freq range) Settings on the Inverter tab are important! Typically the shutdown voltages should be set slightly higher than where the battery BMS would disconnect. Check your battery mfg recommended values, and maybe increase by .3 volts to avoid hitting the BMS disconnect threshold. The inverter should stop discharging, before the battery is totally empty, to avoid manual intervention to restart the system. For a 12v LFP system, here are reasonable settings: (generally multiply by 2 or 4 for 24v or 48v systems, but check your battery manual for specific numbers) Low shutdown 10.4-10.7 (if under load, voltage can be lower at the Multiplus) Low restart 12.1, Low pre-alarm 12.4 (Red shows values that you have changed) Settings on the Charger tab are important! First select Battery type. Likely you have LFP batteries. Then adjust the Absorption voltage, Float voltage, absorption time according to your battery manufacturer’s recommendations. The charge current should be set appropriately for your battery bank size. Typically, with 2 or more LFP batteries, the batteries can handle more than the maximum charging output of the Multiplus 3000, so the default of 120a is good. The default settings on the Virtual switch, Assistants, Advanced tabs should be fine. Save your changes: Choose File, Exit to quit VEConfigure, and it will ask before saving the changes (to the original file name, you don't get to change the name here). Now your file is ready to upload back to the Multiplus via VRM. Upload your changes to the Multiplus, via VRM: Back in the VRM Portal device list, under the Remote VEConfigure option, select the Upload button. Choose the .rvsc file you just modified, and click ‘OK’. The modified .rvsc configuration file will get uploaded to the Cerbo, which will update and restart the Multiplus inverter. Voila! You have configured your inverter settings, remotely! Remote configuration of other devices via VRM with Victron Connect: Typically the Victron Connect app is used on a phone or tablet to configure devices locally, communicating over bluetooth. Once VRM is set up with the Cerbo, any devices that are connected via VE.Direct or VE.Bus can be configured remotely, running Victron Connect on a Windows PC. (Pre-step: Install the VictronConnect Windows program from here: https://www.victronenergy.com/support-and-downloads/software ) Open Victron Connect on your Windows PC. Select the VRM tab on the right, and click on your Cerbo system. On the left, it shows your Cerbo (with a link to your VRM dashboard), and on the right, you’ll see all the other devices on your system. Click any of these devices on the right, and Victron Connect shows the current status and settings under the upper right gear icon, as if you were connected via bluetooth. But you’re magically far, far away! Just click the settings you’d like to change, and click ‘OK’, presto. This works for all smart Victron devices which connect to the Cerbo via VE.Bus or VE.Direct ports. The Multiplus shows up in the device list also, and you can see status, but the configuration settings can not be changed through VictronConnect/VRM. Not all Orion DCDC or solar MPPT devices have VE.Direct ports, so those are limited to configuration locally via bluetooth. Example showing Smartshunt: Alternatively, you can open VictronConnect from the VRM web portal Device List. There are two ways to access VictronConnect from the Device List: Click the Blue oval highlighted button ‘Open in VictronConnect’. This will open and display the system & all devices as described above. Red highlighted buttons: Click one of the Device List ‘+’ tabs, to see more info about that device, (the MPPT Solar Charger is selected below). Then an ‘Open in VictronConnect’ button shows at the bottom. Click that button and VictronConnect opens for just that particular device. So, that’s it. Amazing technology! You can check on your van from far away, and now you can make changes if needed. If you want to help out a friend with their Victron system, now you can do it remotely and come off like a genius. If you purchased your electrical equipment from us (thanks!), you can take advantage of our world-class support including adding service@vanlifeoutfitters.com to your VRM account so that we can help you troubleshoot remotely if needed. Again, that’s one of the benefits of purchasing a Victron system bundle from Vanlife Outfitters; your access to our expert tech support team.
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How To Set Up Remote Monitoring For Your Victron Electrical System
How to set up Victron's Remote Monitoring for your van electrical system. How to invite Vanlife Outfitters to view and assist you with configuring or troubleshooting.
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Troubleshooting Tips: Nations + Wakespeed Secondary Alternator No/Low Power
If your Nations + Wakespeed secondary alternator kit isn’t charging your camper van battery bank, use this post to diagnose wiring, LED states, CAN-bus settings, DVCC behavior, and RPM & temperature throttling. Symptom Likely Cause Quick Fix WS500 LED not blinking yellow/orange or not showing up in Cerbo Devices list Improper CAN bus configuration Check CAN bus wiring (including terminators) and set Cerbo CAN bus to 250 kbit/s. Engine needs to be running No power from alternator Improper wiring, especially Feature-In “white wire” Set BMS relay to Alternator ATC mode Check all wiring versus example wiring diagram Less power from alternator than expected Derating is protecting batteries or alternator Retest with low battery State of Charge Make sure electronics and alternator are appropriately cooled Alternator powering correctly but Cerbo shows “--W” or incorrect DC Load power WS500 configuration issue Ensure that firmware is up to date Check alternator shunt wiring Make sure WS500 Ignore the Local Current Sensor? setting is Off We’re fortunate to have installed, commissioned and supported a ton of Nations + Wakespeed secondary alternator kits in our vans and customer’s rigs. What that really means is that we have experience from making a ton of simple mistakes when powering up these systems. One tricky aspect of the secondary alternator kits is that everything needs to be done correctly, otherwise no power may come out of the alternator. And well, massive power from the alternator is kind of the point. We recently posted a two-part blog series on Powering Up Your Camper Van For The First Time. Part I discusses steps to think about before or during your build, and Part II focuses on the steps to energize & configure your mobile power system. Think of this post as a special addendum for secondary alternator kit power on & troubleshooting, where we touch on common mistakes and quick fixes. Whether your system is 12 V, 24 V, or 48 V, these tips should help you. These tips focus on supported Wakespeed configurations such as Victron NG (or Smart) batteries, and like Part I says…we assume that you’ve double checked your wiring versus our example wiring diagrams. What to check first (30 second triage) Make sure that your BMS relay is set to Alternator ATC (allow-to-charge) mode. This setting can be done via Bluetooth using VictronConnect to your BMS. Without the relay mode configured, your Feature-In wiring isn’t complete. Triple check the wiring connections from the BMS to the Feature-In wire on the Wakespeed harness. If your wiring is wrong, the Wakespeed may be inhibited. Measure the Feature-In wire on the harness and you should see your system voltage when the system is running. Is your Wakespeed LED blinking a steady yellow/orange? If not, your Wakespeed is not in Sync mode to your BMS. Here’s the Wakespeed guide. Check your CAN bus connections and Victron Cerbo CAN settings. Both your BMS and your Wakespeed must be connected to the same CAN bus at the Cerbo. The CAN terminator (black for Wakespeed) is required on the unused Wakespeed port. Make sure that the appropriate Cerbo CAN bus is configured for VE.CAN & CAN-bus BMS (250 kbit/s). If these settings are correct, your Wakespeed will be visible on your Cerbo Devices list when your engine is running. Wakespeed WS500 & WS500 Pro configuration You really should understand your Wakespeed configuration, which is touched on in one of our secondary alternator system posts. With the newer WS500 Pro, either an Android or IOS device can be used. If you’re a customer with an original WS500, then it’s highly suggested to use a low-cost Android tablet for a USB OTG (On-The-Go) connection to the Wakespeed. Using the Wakespeed app, here are some quick checks: Is your firmware up to date? Wakespeed-Victron integration and features have improved over time. The Wakespeed guide linked above notes the minimum firmware version required, but we highly recommend updating both your Cerbo and Wakespeed devices to the latest revision. Make sure that DVCC is enabled on the Wakespeed. Using the Wakespeed app to Configure, in the System tab check that Support Victron DVCC? is ‘On’. Victron Cerbo: What “-- W” or negative numbers mean for alternator power Is your Cerbo reporting “-- W” for alternator power even though you’re seeing charging power into your batteries? Make sure that Ignore the Local Current Sensor? is ‘Off’ under Advanced Options in your Wakespeed app in the System tab. You’ll need to enable Expert Mode in the app settings, but you’ll need to act like an expert and follow Wakespeed’s guidance - don’t touch any of the red configuration fields unless you’ve read the manual and know what you’re doing! Why set Ignore the Local Current Sensor? to ‘Off’? Because two negatives make a positive in this case. You installed a current shunt to measure alternator power, so don’t ignore the current sensor and you’ll be seeing alternator power on your Cerbo! Is your Cerbo reporting negative power from the alternator? Check your gray & purple wires on the Wakespeed harness, and check the inline fuses too. The purple wire connects to the shunt on the alternator side, while the gray wire connects to the shunt on the battery side. If those wires are reversed, your regulator is reading the current backwards. You can either swap those wires physically or use the Wakespeed app to fix it - that’s why there’s a Is shunt backwards? setting in the System tab. Are you getting throttled? More tips for limited output power Make sure that Wakespeed DIP switch 8 hasn’t been inadvertently set to On, which forces the regulator into Small Alternator mode which has reduced power. Are your batteries already charged? If your Victron batteries have a State of Charge above the SoC Threshold in the BMS, then the algorithm controlling charging may be throttling charging power and optimizing your battery lifecycle performance. Don’t fret! Let your battery bank discharge, then try again to see if you’re getting the alternator charging power you expect. Don’t forget that secondary alternator performance is proportional to engine RPMs. Especially if you have 24 V or 48 V secondary alternators with limited idle power expectations, give the engine some gas before testing your output power. Also don’t forget that the Wakespeed Engine Warmup Delay needs at least 30 seconds, so give it some time and then some RPMs! Alternator temperature also impacts charging power. The Wakespeed will automatically reduce field drive and derate the alternator as temperatures increase, which leads to reduced power. You can check the alternator temperature from your Cerbo under Devices. Reduced power may be an expected situation to preserve the lifespan of your alternator! Safety reminder: Your power distribution may be energized by any of your charging sources, not just your secondary alternator. Ensure that all charging sources are disabled before conducting maintenance such as checking wiring. Use caution near hot items such as the alternator or electronics, and adhere to safety warnings such as spinning belts in the engine compartment. Got power now? Yay! If not, then bummer. But don’t worry, feel free to reach out to us because we’re here to help. Our tech support team will happily talk to you about the ways we’ve messed up building our systems. But then we’ll ask for pictures of your system, want you to get connected to VRM, and probably have you start working on a log file. You’ll be happily driving around recharging your system with massive power in no time! FAQ: Getting Power From Your Secondary Alternator System 1. What is the most common mistake in powering on my secondary alternator?Feature-In wiring is the most common issue leading to no power from a secondary alternator system. Check the ‘white wire’ wiring and make sure your BMS relay is set to Alternator ATC mode. 2. How do I connect to my Wakespeed regulator?WS500 Pro users can use Bluetooth to connect with the Wakespeed Configuration and Monitoring Utility App (IOS or Android). WS500 users require a physical USB connection using the App (Android) or software on a Windows PC. A low-cost Android tablet is highly recommended! 3. What are the Wakespeed LED blink codes?The Wakespeed regulator has a multi-colored LED. Somewhat surprisingly, a blinking yellow/orange LED is the desired blink code. Green LEDs means that your Wakespeed is not in Sync with your Victron Cerbo - check your CAN wiring and Cerbo CAN bus configuration. Red flashes are Error/Advisory codes - use the Wakespeed manual to identify the blink code and start troubleshooting. 4. Why am I getting reduced power from my Nations + Wakespeed system?Typical reasons to get some, but not full, power from your secondary alternator system are temperature derating, high State of Charge (SoC) on your batteries, and incorrect expectations of idle power. 5. Why does my Cerbo show “--W” for alternator power?The system needs an alternator shunt to measure alternator power, so that’s one reason we highly recommend wiring in a shunt. To see the shunt measurements on your Cerbo, make sure that Ignore the Local Current Sensor? is configured to ‘Off’ using the Wakespeed app. Related Resources Powering Up Your Camper Van Electrical System The First Time!: Part I and Part II Secondary Alternator System Blogs and Diagrams: 12 Volts, 24 Volts, and 48 Volts Nations + Wakespeed Secondary Alternator Kit and Electrical System Bundle Wakespeed basic configuration video
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Kick The Tires And Light The Fires: Turning On Your Camper Van Electrical System For The First Time! Part 2
If you’re building a camper van electrical system, or planning your vanlife power setup, the first power-up is a big milestone. This blog is Part II of a two-part series on powering up your camper van electrical system for the first time. Part I discusses steps to think about before or during your build, and Part II focuses on the steps to energize & configure your mobile power system. To be honest, planning for & commissioning your electrical system is a process, so if you missed Part I, give it a read first before diving in here. This blog hopes to provide some of the why to go along with the what when commissioning your electrical system. Your build is progressing, and you're almost ready to Turn. It. On. Does it feel a bit daunting? Turning your electrical system on for the first time can be as exciting as putting that first hole in your new rig. How many times did you measure before you cut? Working methodically to power your system on is the same idea! It's going to be okay, and here is a checklist for getting your system up and running. Every system is different, and you can find a bunch of different how-tos on the interwebs. Some manufacturers provide commissioning steps in their manuals too, as an example this procedure is a good list even if you don't have a Victron BMS. You did read the manuals for your equipment, right? Here’s our take on a solid approach to getting your electrical system up and running. Double check At long last, can we finally get on with the steps? Yes, of course, as long as you consider checking your connections as part of the turn up sequence. Incorrect wiring can cause damage. This section is called double check, but we really mean triple check. Step 1 - Test Your Lugs, Terminals & Ferrules Check that your lugs and ferrules are done properly. You are not trying to treat those connections with "kid gloves" either. If you can yank on a lug and it comes off, that's not good! You're relying on those connections to handle high currents and keep you safe. Lugs, ferrules and terminals should be secure and difficult if not impossible to remove with a simple pull. Let’s briefly touch on ferrules too, which can be new or difficult for some customers. Since tinned, stranded wire from brands like Ancor is preferred for environmental & vibration tolerance (e.g. your safety!) in mobile power systems, wire ends for screw terminal connections should use a ferrule. Generally, a hex ratcheting ferrule tool is preferred, as the round shape formed after the crimp fits best in most screw & spring clamp terminals. In some cases, for instance with the Orion XS DC-DC chargers using the recommended 6 AWG wire in our free example wiring diagrams, only a hex crimped ferrule will fit (and a square crimped ferrule will not due to the resulting shape). The Victron Multiplus II inverter/charger AC terminal blocks require 18 mm bootlace ferrules that are longer than what is provided in most ferrule kits, and using shorter ferrules may cause the terminal block spring clamps to come loose. Do yourself a favor and use the correct ferrules, even if you need to go replace a few connections before powering on your system. Part of double checking can include learning that a few minor changes can go a long way to improving the safety and reliability of your system. Step 2 - Properly Tighten Your Connections Not only do your connectors need to be done properly, but those connections must be tightened properly. Properly means that you're not a tire jockey tightening nuts with your air wrench! Whether it's Victron, Blue Sea, or any other manufacturer, your device manual provides torque specifications for the connections. So, please use a torque wrench! Step 3 - Review Every Connection in Your Wiring Diagram Review your wiring diagram. Review our complete set of example wiring diagrams. Depending on your system, you may use sections from more than one diagram. We recommend printing out your diagram(s), then highlight each wire & connection as you go through the double check on your system. While you're in the diagram, you did note all of the case & chassis case grounds, right? These safety connections are not optional. Check your MPPT case ground, your Multiplus PE connection, and of course your vehicle chassis ground connection. Step 4 - Check Your Fuses & Breakers Are all your fuses and safety devices installed? Remember that a fuse is sized to protect the wire. Double check that the correct fuse rating is installed in every location. Check your circuit breaker sizes too, and since we're almost ready to turn things on, go ahead and flip those breakers to the off position for now. Here's a quick tip for the Lynx Distributor: if you're not using every Mega fuse position in the Distributor, the LED will remain orange and not a happy green. With a Lynx Shunt or Lynx BMS connected to a Lynx Distributor, an empty Mega fuse slot will show up as an alarm because a blown fuse (i.e. an open fuse) looks no different than a missing fuse. We recommend mounting spare fuses in your unused Mega fuse slots. Hopefully you'll never need them, but maybe you'll be glad to have one handy in the future. Step 5 - Test Wiring with a Multimeter Use a multimeter to triple check those connections. Just to be clear, we're doing all of these checks before the system is energized! Check each load branch wiring for no "dead shorts", where the power and ground wires should show resistance and not be shorted together. Same for the AC wiring, where the hot and neutral should not be shorted. (Keep in mind that a Multiplus inverter/charger contains a ground relay that automatically connects neutral to the chassis ground if no AC input is supplied, so those AC wires may read as shorted.) Step 6 - Wrap It Up As you are wrapping up your double checks, it’s a good time to cover any exposed terminals to prevent damage from any accidental tool drop. Dress your cables with cable ties to minimize vibration and torque on equipment connections. Checklist for your wires and safety devices Test & inspect that you properly crimped your lugs, terminals, and ferrules Check that your connections are torqued to manufacturer specifications Review your wiring diagram and mark off that all wiring connections are as intended Check that your fuses & breakers are sized properly Test wiring for shorts & opens using a multimeter Install cable housings and cover any exposed terminals Finally! This is the moment where it all comes together. Start will all equipment switches turned off. Make sure the master battery switch or contactor in your BMS is off. If needed, temporarily remove fuses to keep sources and loads un-powered. Make sure your Multiplus inverter/charger switch is in the off position. As a reminder from Part I, we’re presuming that your batteries are fully charged before reaching this step. Work methodically! If something doesn't look right as you go through the steps, stop and assess. It's okay to power down, make a fix, and start over. And if you listened to our guidance for working on a testbed prior to a full camper van system, do as many steps as feasible...then get back to testing & building that rig! Here is our recommended turn-on procedure: 1) If your batteries have an on/off switch, go ahead and turn them on. If your system has a BMV-712, check your battery bank voltage now. Also check your battery using the manufacturer’s app if it has Bluetooth support. You’re looking to confirm that the batteries have no alarms and show very similar voltage readings. This tells you that your battery bank is successfully connected and ready to serve as an energy source for your system. 2) Turn the master switch or contactor on. Use a multimeter and check the voltage on your Lynx Distributor, it should (nearly) match your charged battery voltage. Use the battery and/or BMS app to check the battery voltage, current (should be a low number), and status. If you haven't already, make sure your battery BMS firmware is up to date. Some customers with a Victron BMS may run into a snag here and notice a pre-charge error. The BMS can be sensitive to capacitance and loads, particularly in complex systems with a Multiplus inverter/charger, a secondary alternator, or many other connections on the Lynx Distributor. If you get a pre-charge error, first check for real problems such as a short or incorrect connection on the distribution. If the connections are okay, you may need a simple workaround to sidestep the pre-charge error. One method is to enable one of your charging sources (see Step 4) to power-on the distribution side of the BMS before enabling the BMS contactor. This workaround pre-charges the distribution with a source other than the batteries through the BMS, therefore the BMS will correctly finish its turn-on sequence with no errors. Most customers can leave their system in on or standby modes after the commissioning steps are complete, so the pre-charge workaround is just a temporary annoyance. 3) If you have a Cerbo GX, it should be powered-up through your distribution. On your touch screen or app, check your Devices list and make sure your battery monitor is reading properly. This confirms that your shunt connection (either VE.Direct to a SmartShunt or CAN to a BMS) is correctly done. If your batteries have "Victron communications", also check your Cerbo Devices list to verify that your battery(ies) are present. You may need to change the CAN bus profile setting in your Cerbo GX to match your batteries and get Victron communications established. 3plus) Give your Cerbo GX some internet access! This step helps provide troubleshooting information for all the subsequent steps and makes it easy for you (and easy for us to help you). Ultimately, get access to your electrical system using the VRM as discussed in this blog. Using the touchscreen, connect to a WiFi network and set up the VRM. Make sure your Cerbo has the latest firmware. 4) Turn on charging sources one at a time. The order of charging sources to enable is not critical, but we suggest prioritizing the Multiplus inverter/charger, solar, DC-DC charger(s), then the secondary alternator kit. For each charging source, use the following steps: Check your battery monitor. Charging current should increase (and be a positive value) when the charging source is on. Check your Cerbo Devices list to make sure the device is communicating with your system. Update the firmware. Check and/or update the configuration to match manufacturer specifications. Periodically check your cables by hand or with a thermal imager. When charging heavily, some cables may be warm to the touch but not crazy hot. After checking one charging source, turn that source off and iterate on a different charging source. Keep it simple and methodical to safely check each part of your system. Once you've individually checked out each charging source, then you're ready to turn on multiple charging sources. There are some things to watch out for when turning on your charging sources. Apply battery power and turn on your Multiplus before connecting shore power. Here are some tips for programming your Multiplus. Charger settings: The devices do not come preconfigured for lithium batteries, so change that charge profile! Inverter settings: We recommend that the low voltage shutdown thresholds are set slightly higher than your BMS low voltage disconnect value. The inverter should turn off before completely discharging the battery bank, which could turn off your entire system. General settings: The default AC input current limit is 50 Amps, which is too high for most DIY garages & driveways using a standard 15 Amp household receptacle. Set that current limit before applying shore power, and let's not pop your circuit breaker or potentially damage your shiny new Multiplus, please?! We touched on solar in this blog. Your Victron MPPT PV (photovoltaic) voltage must be 5 Volts higher than your battery voltage for a charge cycle to start. Check that your alternator-based charging sources turn off when the engine is off but turn on when the engine is on. You want to ensure that your camper van starter batteries are not depleted by leaving a DC-DC charger on with the engine off. Our Victron & Sterling DC-DC chargers can be configured to detect voltages, detect vibration, and/or utilize external "remote" on/off connections to keep your van's two battery systems properly isolated. VictronConnect tip: After connecting to a MPPT or DC-DC converter via Bluetooth using the VictronConnect app, if your device is powered on but in the off state (i.e. not charging), you will see a Why is the charger off? line on the status page. Victron tells you the reason your device isn't charging, and that can be pretty handy! Even with your battery switch or BMS contactor open, any charging source that is enabled will energize your Lynx Distributor. Why? Because your charging sources and your loads are interconnected on your distributor. Your master battery switch or BMS contactor separates energy stored in your battery bank from the distributor but does not disconnect the other sources of power. Be cautious while testing or doing maintenance, and make sure that all batteries and charge sources are off when required. DVCC tip: DVCC is an algorithm running in your Cerbo that intelligently coordinates your smart charging sources to provide only the charging current desired by your batteries & BMS. It's not quite magic, but testing with DVCC enabled can yield confusing results. Typically, if your batteries are mostly full (above the SoC threshold, State of Charge in your battery monitor), then your charging source(s) may be throttled to optimize battery lifecycles. Don't panic if your DC-DC charger doesn't put out a full 50 Amps in that case. Another source of throttling is heat, so testing mid-summer in high ambient temperatures may limit charging performance. You may need to move on to the next step, enabling loads to discharge your battery bank with charging sources off, then return to re-examine your charging performance with a lower battery SoC. Need troubleshooting help? Don’t forget the cutting it in half approach as discussed in Part I. Our tech support team has tons of vanlife experience, so we’re here to help too. 5) Turn on loads one by one. Work through your checklist of all AC and DC loads. For each load, check with a voltmeter and look at your battery monitor or touch screen display. You should see an appropriate increase in AC or DC Wattage for each load. If your load reporting looks incorrect, double check your cabling, especially the chassis ground. Only the battery cables should be on the Battery Minus terminal of your BMS & shunt, and every other connection (like chassis ground!) should be on the distributor side. As with your charging sources, inspect your distribution and load cables & connections for excessive heat. 6) Check your battery monitor (i.e. shunt). Now that you can comfortably charge and discharge your batteries, make sure that your battery monitor is properly configured. In Victron-speak, you want to allow a successful synchronization so that the battery monitor correctly reports your SoC. After the first power up, the battery monitor may not show the correct SOC. To reach a synchronization (which can be checked using the VictronConnect app under History), first discharge the batteries to around 50% SoC using your loads, then turn off your loads and charge the batteries to 100% using a charging source (such as shore power which typically provides the fastest charging). Allow your system to complete a full lithium charging profile, transitioning from absorption (higher, constant current) to float (low current, constant voltage). If your battery monitor reports 100% SoC and shows a synchronization event, your battery monitor is properly configured and will provide correct SoC reporting. This step also ensures that any paralleled batteries in your battery bank are balanced, promoting equal sharing of the charging sources and loads from your batteries to prolong battery lifecycles. 7) Use your system and enjoy! Take advantage of the VictronConnect app and VRM to monitor your system performance. While this blog is about turning on your system for the first time, many customers are already thinking ahead about maintenance & battery storage. Self-discharge of lithium batteries is quite low, so typically we recommend that you don’t need to completely turn off your system when not in use. If you have internet access and are using the VRM, then leaving your system on and idle is quite helpful for remotely checking in on your rig. You may find it handy to turn your Multiplus inverter/charger to Charger mode, which disables the inverter and saves you the 20-30 Watts of idle power from being constantly consumed while you’re not using your system. To maximize your battery lifecycles, it’s recommended that lithium batteries are stored between 50%-70% SoC. Most importantly, lithium batteries have improved lifecycles when not exposed to high currents near 100% SoC. In other words, don’t leave your system plugged into a charging source constantly with your batteries at 100% SoC. If you have a system with Victron NG or Smart batteries with DVCC enabled, the good news is that your system is automatically being optimized and you don’t need to take any special storage precautions. Victron automatically keeps the SoC optimized while allowing charging to 100% once per month, which keeps the battery cells balanced. For more basic or value battery-based systems, you may need to be a little more mindful about lithium battery storage. You may wish to manually enable/disable charging sources to manage your battery SoC. If you can store your electrical system with shore power, an alternative is to adjust your configuration profile to a lower absorption voltage that will limit charging to around 70%. Don’t forget that you need to charge up to 100% every month or so to keep those battery cells balanced. Change your system configuration into normal mode to allow charging up to 100%, then return to a storage mode configuration until you’re ready to use that rig. Don’t forget to change back to normal mode to get the most performance out of your electrical system while you’re on that trip! Super-condensed power-on checklist Start will all loads and charging sources off Pre-charge your batteries and make parallel connections before turning batteries or battery switch on At each step of your power-on, use your device’s Bluetooth app and a multimeter to check status & power. Also check for excessive cable heating Use your battery monitor to check battery voltage, status, and current Update firmware on each device as you go If applicable, use your Cerbo to check that device communications are established. Set up your Cerbo VRM for remote monitoring and troubleshooting Turn on charging sources one at a time. Test each charging source by itself before using multiple charging sources together Turn on loads one at a time After checking your charging sources and loads, take your system through several discharge then charge cycles to balance your batteries and synchronize your battery monitor Don’t forget that storing & maintaining your batteries should be done at a lower State of Charge than your typical 100% pre-trip SoC Summary Successfully powering up your camper van electrical system for the first time is all about being methodical. There are four major steps in planning for & commissioning your system: Prepare your batteries Get familiar with your system with bench testing & incremental building Double check your wiring and connections Power up your batteries, charging sources, and loads in an orderly fashion, checking for voltage & heat at each step. Configure each device as you go. FAQ: Commissioning & Configuring Your Camper Van Electrical System What should I check before powering up my electrical system?Inspect every lug and ferrule, check torque specs, confirm correct fuse ratings, and use a multimeter to ensure there are no shorts between positive and negative wires. How do I safely turn on my camper van electrical system for the first time?Start with all switches off. Confirm battery charge and all connections before powering up. Power on your batteries then the master switch. Verify voltage before enabling charging sources or loads. How do I configure my Victron Multiplus inverter/charger for lithium batteries?Use the Victron VEConfigure software to change the charge profile to lithium, set inverter low-voltage shutdown slightly above your BMS cutoff, and reduce the AC input current limit to suit your shore-power source. What recommended order should I turn on my charging sources?Start with the Multiplus inverter/charger, then solar MPPT, DC-DC chargers, and finally any secondary alternator kit. Test one at a time before enabling them together. Why is my Victron BMS showing a pre-charge error?This can happen when capacitance or load prevents proper pre-charge. First check that there are no shorts on your Lynx Distributor. Enable one charging source to energize the distribution side before closing the BMS contactor, then retry. How do I synchronize my Victron battery monitor (BMV-712 / SmartShunt / Lynx Shunt / BMS)?Make sure to use a lithium-ion charging profile on your charger. Discharge batteries to ~50% SoC, then fully recharge until absorption transitions to float. Once the monitor shows 100% SoC and logs a “synchronization” event, calibration is complete. This can take some time, so be patient. How should I store lithium batteries in my camper van? Keep between 50–70 % SoC, avoid continuous charging at 100 %, and store in moderate temperatures. Systems with DVCC or Victron Smart / NG BMS manage this automatically.
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The Calm Before The Storm: Powering Up Your Camper Van Electrical System The First Time! Part 1
If you’re building a camper van electrical system, or planning your vanlife power setup, the first power-up is a big milestone. This blog is Part I of a two-part series on powering up your electrical system for the first time. Part I discusses steps to think about before or during your build. We hope you’ll give this a read, hopefully before you need Part II that focuses on the steps to power up & configure your mobile power system. To be honest, planning for & commissioning your electrical system should be an iterative process, so give both parts a read and let’s get to it. This blog hopes to provide some of the why to go along with the what when planning for your camper van electrical system. Planning for that first power-up involves two major pieces. One step is having your batteries charged & ready. The second step is a bit more involved, and that’s thinking ahead (thus the planning keyword) and gaining familiarity with your equipment as part of a testbed. Prepare your batteries We recommend charging your batteries before wiring them into your camper van electrical system. If you have batteries in series (not something we recommend often at this point with great battery options available at 24 and 48 Volts), then charging the batteries & balancing the internal cells is required. Here's an excerpt from Victron on why, and yes this is a prod to Read. The. Manual. for all of your equipment. The Victron manuals are an exceptional resource, and reading through your manuals makes sure that you understand the features, installation requirements, and safety guidelines for your equipment. When using batteries in parallel, it's still a good idea to charge them first. Charging those batteries individually is a good idea too. After charging, check each battery’s voltage with a multimeter to confirm that they are at the same voltage. It’s typically not possible to get them exactly the same, but charging with 0.1 Volt (closer is better!) is sufficient. Charging each battery separately to the same voltage helps minimize current flow between batteries when they are later connected in parallel, which is important to prevent damage caused by high currents from connecting different voltages. Lithium batteries are not shipped fully charged, so charging your batteries also provides more capacity so that you don't feel rushed during the steps covered later in this blog when turning on your equipment. Deeply discharging your batteries, also referred to as undervoltage, can be damaging to lithium batteries (moreso than overcharging that is typically protected by the BMS!), so there's another reason to give yourself plenty of margin during your turn on process. It's critical that your batteries are charged with a proper charge cycle, and the batteries should be charged through your Battery Management System (BMS). If you have selected batteries with an external BMS, that means you need to connect your battery and BMS to charge each battery. Whether your lithium battery has an external or internal BMS, use a charger with a lithium-ion profile and be careful to monitor temperature and overcharging during this step. This is a perfect segue into the next step (or is it the first step?!), which is working on a testbed for your electrical system. If your batteries have Bluetooth and an app, this would be a good time to use it. Connect to each battery and look at the status. Do your batteries say fully charged (100% State of Charge, SOC) and balanced? Yay! Some customers find it easiest to use an external battery charger to initially charge their batteries. Using an external charger is simple - just plug into a standard AC receptacle for power and allow each battery to go through a complete charge cycle (go through a bulk stage and get to the low current float stage in lithium batteries). If the compelling reasons to build a testbed below don't sell you, then an external battery charger may also be your best option to get those batteries charged before turning on your system. Our recommendation is to combine a test setup with your initial charging step, and use one of your system charging sources (particularly your Multiplus inverter/charger) to initially charge each battery. More on that now... Checklist for preparing your batteries Charge each battery individually using a full lithium-ion profile Use a multimeter to check each battery voltage Confirm BMS status and 100% SoC using the Bluetooth app Testing, testing, 1, 2 This camper van build is already a ton of work, and now you're suggesting that I build it twice!? To some degree, yes. If you're finding this blog after your build is done, then you could skip this section. Hopefully you'll read on and see why testing early is important and helpful. Bench testing doesn't mean that you have to build a complete system either. Go piecemeal. Our recommendation is to slowly add one piece of equipment at a time. Start with your batteries and BMS, add your Distributor, add a charging source, then turn add & turn on a load. Continue that methodical approach with other charging sources & additional loads. If you choose, test something then tear it down and test something else. You don’t need your testbed fully functioning, for example it’s okay to add a DC-DC charger or MPPT without the “source” connection. Your device will still turn on once energized, and you can start using your equipment and complete the configuration step. The whole point is to get familiar with your (future) system. Why bench test? Practice the physical connections. This is your chance to get familiar with the connections on your equipment. Many customers are stripping, crimping, and properly torquing cables for the first time. It's perfectly reasonable to throw away a test lug or two...aren't you better at something after a little practice? Particularly with the high current connections in these electrical systems, it's important that the connections are done properly. Learn that your layout can be improved. After assembling some of your equipment, it's just easier to visualize how it all fits together. How do I minimize my battery cable lengths? Gee, these 4/0 cables need a bend radius. Maybe a ML Link would be easier than a cable? Oh, the touchscreen cables aren't long enough, and it needs to be closer to my Cerbo. These are just some examples of lessons learned that are easier to resolve before your build is underway. Forget something? Testing and using your equipment before your build is "done" can reduce your panic later. Need fuses for your Lynx distributor? Need an extra VE.Direct cable so your equipment can communicate? Have everything in imperial (SAE) but one item has to be metric...and you're off to the store again. It's easier to troubleshoot and resolve issues in a testbed. Moving cables, accessing equipment, or even starting over is so much simpler before the equipment is installed in your rig. And if you’re following our advice to incrementally build & test equipment, problems are presented immediately with an obvious example of cause and effect. The manufacturer says so. We've already discussed why you should charge your batteries first. Nomadic says "always bench test AC unit before installing". Other vendors do too. Yeah, we know, those annoying manuals again. Work through failures early. Yes, we had to go there. Sometimes a mistake is made, and you need a new fuse, or worse, a new piece of equipment. Didn't notice some shipping damage inside the box? Some unlucky few experience the dreaded Dead On Arrival equipment, which is quite rare but a super bummer to deal with. Find out early by bench testing, and don't wait until you're rushing to be ready for that first road trip. Consider purchasing a small power supply (bonus tip: the external battery charger discussed above can also operate as a power supply to run DC loads). With a power supply, you can test easily without worrying about your battery cycles. Run your water pump and test those fittings, get familiar with your Cerbo and get the VRM ready for troubleshooting, trial your LED lighting or dimmer switches, the list is endless, but building familiarity with your equipment will save time & heartache later once it's in your rig. If you're still not sold on a separate testbed, then at least consider building and testing your system incrementally rather than all at once. It's so much easier to isolate problems when something works, you add a piece of equipment, then something doesn't work. That narrows down your focus to what's new rather than staring at a complete system with no clue as to where to begin. These electrical systems can be complex, and despite a methodical approach some problems may not be easy to identify. In case you run into problems, here’s a super secret (not really) testing tip: make a complex problem easier to solve by cutting it in half, meaning make methodical changes to remove components and narrow down the potential problem. This is also called divide and conquer. Some ways to cut it in half may be to: Remove charging sources one by one. If the problem persists, a removed source isn't likely to be your problem, or if the problem is resolved, that recently removed source may be your issue. Remove loads one by one. Same idea as removing charging sources: is a particular load causing you trouble? Replace a source or a load with an identical copy. This approach can help rule out physical or device problems, but be careful that software or configuration of many devices can be related to the problem. If you replace one device with an identically configured copy and the problem changes, then you're making progress towards finding the culprit. If you replace one device with an identically configured copy and the problem doesn't change, you may not have learned anything, or maybe it's time to try configuration changes. Change firmware versions or software configuration items one at a time. Change, test, repeat. Change, test, repeat. If you change 27 settings at one time and something behaves differently...did you identify the problem or just change the scenario? Or even if you did come across a configuration setting that was important, which of those 27 settings was the one? Whether you’re working on your testbed or in your rig, our tech support team is always available to help you, and you don’t have to wait until you’re “done” to reach out to us. In fact, it’s probably easier on you and us if you’ve been working methodically and have more info to get us started than ‘it’s broke,fix it’. The bottom line is that after building a testbed you're going to be better at doing something the second time than the first. You’ll be comfortable with your equipment, you’ll have confidence in your system, and you’ll be off enjoying vanlife on your first road trip sooner by planning ahead before powering up your system for the first time. Common mistakes to avoid Not using bench testing to improve your van’s build - practice those connections first, and any bench test error is simply a “lesson learned” that will make your build better and safer Building out everything, then being overwhelmed about where to start - it’s okay to be methodical and build confidence in yourself as you incrementally build & test your system Making access for maintenance difficult or impossible - connections need to be periodically inspected, or maybe you realized that a mistake was made during commissioning. Do yourself a favor and plan ahead for the capability to access & inspect your equipment after install. Summary It’s important to plan ahead before powering on your camper van electrical system for the first time. Charging your lithium batteries fully with a proper charge cycle gets you prepared to start connecting other equipment. We suggest you work methodically and consider a testbed prior to your van build, or alternatively build & use your power system iteratively. Using a testbed helps you: practice the physical connections plan an optimal layout of your components configure and test your equipment make it easy to troubleshoot issues Next Step Ready to power up? Check out Part II for step-by-step guidance on commissioning and configuration. FAQ: Powering Up Your Camper Van Electrical System for the First Time 1. Why should I charge my camper-van batteries before installation? Lithium batteries are typically shipped partially charged, not full. Charging them before installation ensures all cells are balanced and the voltages match across batteries. This prevents high current surges when connecting them in parallel and gives you full capacity when testing or powering on your system for the first time. 2. Do I need to charge each lithium battery separately? Yes – it’s best to charge each battery individually until their voltages are similar, at least within about 0.1 Volt of each other. Doing this minimizes current flow between batteries when connected in parallel and reduces stress on your system. It’s also a great opportunity to verify that each battery and BMS is functioning properly. 3. What’s the safest way to charge lithium batteries for a van build? Use a charger designed for lithium-ion profiles and always charge through the Battery Management System (BMS). Monitor temperature and voltage to avoid overcharging. Many builders use an external charger or their inverter/charger (like a Victron Multiplus) to perform the first full charge. 4. What is “bench testing” or a “testbed” for a camper-van electrical system? Bench testing means assembling and powering your electrical components on a workbench before installing them in your van. It lets you practice making cable connections, confirm proper wiring, configure settings, and verify that devices communicate and operate as expected. This reduces installation surprises and makes troubleshooting far easier. 5. How do I build a simple testbed for my van electrical system? Start small. Connect your batteries and BMS first, then add one component at a time – a distributor, then a charging source, and then loads. Power up each addition separately to confirm correct operation. You can use an external power supply to run loads without cycling your batteries. 6. What are the benefits of testing my system before full installation? Testing early helps you: Practice safe, solid cable terminations Optimize layout and cable lengths Confirm that your components communicate properly Catch missing parts or incompatibilities Identify defective equipment before it’s permanently installed 7. What are common mistakes when turning on a van electrical system for the first time? Skipping the initial battery charge and balance Connecting batteries with mismatched voltages Over-tightening or under-torquing high-current connections Failing to label or document cable routes Powering up everything at once instead of one step at a time 8. How can I troubleshoot issues during the first power-up? Take a divide and conquer approach: Remove charging sources or loads one at a time to isolate the issue Replace a suspect component with a known-good on. Revert firmware or configuration changes step-by-step Use your device apps (e.g., VictronConnect or VRM) to check for abnormal readings 9. When should I reach out for help with my van electrical system? If you’re unsure, don’t wait until something goes poorly. Contact our Technical Support Team before you’re “done.” We can help confirm settings, review the manuals, and troubleshoot issues faster when you’ve been testing methodically.
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How To Choose Solar Panels For Your Camper Van
This blog details the steps we suggest to pick solar panels for your rig. First step, play Tetris! How much space do you have available for solar panels on your roof? Start by determining if you will be mounting your solar panels to a roof rack, OEM roof rails with crossbars, or some other method. Mounting solar panels using Z brackets to crossbars is our go-to approach. Take away space for your vent fan(s), rooftop air conditioner, Starlink mount, recovery boards, rooftop deck, or other rooftop accessories. That remaining space (hopefully there is some left over!) can get filled with solar panels. Just like all of the tradeoffs inside your rig, you have to make tough decisions on what can fit on top too. Here’s the part that’s not as much fun as it sounds: play panel Tetris, looking at the dimensions of the solar panels while trying to maximize the usable space. Different vendors may have different dimensions for the same panel wattage. Roughly speaking, you will find that panels with lower wattage ratings are correspondingly smaller. Remember that you’re trying to maximize the rooftop area covered with panels, so selecting a smaller panel may allow you to fit more total wattage on your roof. Also keep in mind that mixing different panel sizes is not recommended, so you’re trying to maximize the number of identical panels to fill up your rooftop space. We find that solar arrays like this Newpowa 220 Watt panel with the long side dimensions of <57″ fit well to maximize the horizontal rooftop space on a van. Because of all those other must-have items, many customers may settle for a 400ish Watt array using two panels mounted horizontally. The good news is that the above steps are where all the tough decisions have to happen. The rest is “easy”. Tetris cheat sheet: get out your graph paper, sketch your roof, and see what fits. 42.3" x 21.3" 100 watt Newpowa 12v Black 45.5" x 30.1" 180 watt Newpowa 12v 52.4" x 30.1" 200 watt Newpowa 12v 61.7" x 28.0" 200 watt Newpowa Pro 12v Black 52.8" x 30.1" 200 watt Newpowa 24v 56.7" x 30.1" 220 watt Newpowa 12v Let’s talk about panel voltage Solar panels are marketed in 12 V and 24 V options. One manufacturer’s 12 V nameplate does not mean that another manufacturer’s 12 V specifications are identical, and in fact those specs can vary greatly. 48 V options in solar panel sizes fitting vehicles are not readily available at this time. You picked a 12 V battery bank, you picked a 12 V inverter/charger, so naturally you pick a…well sorry to confuse you, but with solar panels the nameplate voltage doesn’t really matter. What does matter are a few details: The specifications of the solar panel, particularly the Voc, or the open-circuit voltage which is the maximum voltage that the panel will produce How the panel(s) are wired, in series or parallel. Wiring panels in series increases voltage, and wiring panels in parallel increases current. Hopefully a quick set of examples will clarify this confusion. Take a look at the Newpowa 200 Watt 12 V panel specs, and compare those specs to the Newpowa 200W 24 V panel. The 12 V panel has a Voc rating of 24.34 Volts, while the 24 V panel has a Voc rating of 48.68 Volts. You may be thinking those voltages are so high, how can either of these panels work with my 12 Volt electrical system!? The key is that the MPPT charge controller converts the PV (photovoltaic, i.e. solar) side voltage to your BATT (battery) side voltage. In fact, you want the PV side to be a high voltage to allow smaller cables, minimize voltage drop, and minimize losses. Can I use 24 V solar panels in a 12 V system? Yes. Using a 24 V panel like the Newpowa 200 W 24 V panel in a 12 V system allows you to either use panels in series for more efficiency or use panels in parallel for better partial shading performance (or both! two series panels with two more series panels in parallel). In a small solar array, even using only one 24 Volt panel can still work well for a 12 V system. Can I use 12 V solar panels in a 24 V system? Yes, with a caveat or two. In order for the MPPT charge controller to start a charging cycle (in other words, for the MPPT to become a useful device by turning on and supplying power to charge your batteries) the PV voltage must be higher than the BATT voltage. In Victron MPPT charge controllers, this voltage difference must be more than 5 Volts. Using two or more Newpowa 200 W 12 V panels in series meets that requirement in a 24 Volt system, as the PV voltage becomes much higher than the nominal battery voltage. Can I use 12 V or 24 V solar panels in a 48 V system? Yes, with the same caveats as above. Especially with 48 V systems that are typically paired with a secondary alternator kit to rapidly recharge while using a rooftop air conditioner, there may not be tons of space on the roof for solar. That’s just one of the tradeoffs when selecting a 48 V system. Solar arrays with three or more 12 V panels in series or two or more 24 V panels in series are typically required in 48 V systems. Picking a MPPT charge controller Victron MPPT charge controllers have two numbers on each device (for example, 100/50), and here’s the breakdown on those numbers: The first number is the maximum voltage that the controller can tolerate. Do not exceed the nameplate voltage rating or device damage may occur. Also note that the Voc rating discussed above is a nominal value, and the actual maximum voltage varies with temperature. Each solar panel manufacturer provides an additional rating for temperature coefficient for Voc (or another similar name & specification). The second number is the maximum current that the controller can source to your batteries. If you have more solar power available than the maximum current rating, no damage occurs but you don’t get to use all of the available power. Because our solar panels are seldom oriented perfectly at the sun, and you only get so many days of ideal solar panel per year, a slightly undersized MPPT charge controller may not be noticeable to your charging performance. These two MPPT numbers sound a little complicated, so use a cheat sheet. And by cheat sheet, we mean this great MPPT calculator from Victron. Here’s the best way to use the MPPT calculator: 1) Start typing your solar panel vendor and SKU in the Solar Panel field. If you’re in luck, your solar panel model is already in the list. If not, try 1a. 1a) Okay, your model didn’t show up. No problem! Find the Advanced Panel Settings slider and enable advanced mode. 1b) Act advanced. Seven panel specifications become available for editing, and for most manufacturers you need to copy & paste those seven specifications from their panel datasheet to the calculator. Pretty advanced, huh!? 2) Set your system Voltage to 12/24/48. This setting is your battery voltage, because we already told you panel voltage is pretty meh 3) Adjust the Series and Strings parameters to yield the number of panels you can fit. Series is obvious, increase this number if you need/want panels in series. Strings means parallel, increase this number for more Y-branch connectors and panels in parallel. It’s okay to play around with these settings too, adjust series or parallel values and see what the calculator tells you. Some panel configurations offer you a tradeoff, while others just require you to wire your solar array a specific way to make it work. 4) Bonus choice: set your location to see an estimate of how much daily yield your solar panel may provide. But you’re in a van and traveling the world, so maybe you care more if it’s going to rain tomorrow than what your yield would be if you parked in Albuquerque for a month? Now look on the right side of the calculator for the Result. Victron tells you the best MPPT charge controller for your array, and they show you lots of fun details why it’s the best controller too. Yay! For some customers, especially those on larger rigs like trailers, going with two MPPT charge controllers with two types of panels may be a useful choice to maximize area. Using two MPPT charge controllers is also a good choice for “ground deployed” solar panels that get temporarily set up in conjunction with fixed rooftop panels. And, you get to play Tetris and use the calculator twice. Fun times. Wrap up Maybe you’re the TL;DR type, but we hope you read through the details above. To wrap it up, we suggest the following steps to pick your solar panels: 1) Play Tetris with your panels to fit as many identical panels as possible on your roof 2) Use the MPPT calculator to select your charge controller That’s not hard! But if you run into any snags, our tech support team is always ready to help you understand more about our solar products and blogs. Contact us!
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Watt Hours Vs Amp Hours
Watt-Hours vs. Amp-Hours: What Every Van Builder Needs to Know If you’re building your own van’s electrical system, you’ve probably seen batteries advertised in amp-hours (Ah), while solar panels and appliances often list power in watts or watt-hours (Wh). Here’s the problem: mixing these up can lead to a seriously undersized system — and that’s how you end up with a dead fridge, no lights, and warm beer halfway through your road trip. By the end of this post, you’ll know exactly what these terms mean, how they’re connected, and how to use them to plan your off-grid electrical setup with confidence. Amp-Hours: The Current Over Time An amp-hour (Ah) is a measure of how much current a battery can deliver over time. Think of amps like the width of a water hose — the bigger the hose, the more water (current) can flow. Amp-hours tell you how much total flow you get over a certain period. Example: A 100Ah battery could, in theory, supply: 1 amp for 100 hours 5 amps for 20 hours 10 amps for 10 hours Key point: Amp-hours alone don’t tell the full story — you also need the voltage. Watt-Hours: The Real Energy Number A watt-hour (Wh) measures total energy — this is the true “fuel tank size” for your battery. Here’s the connection: Watts = Volts × AmpsWatt-hours = Volts × Amp-hours So if you know a battery’s amp-hours and voltage, you can find watt-hours. Example: 100Ah at 12 volts = 1,200Wh 100Ah at 24 volts = 2,400Wh Why it matters:Two batteries can have the same amp-hour rating but store very different amounts of energy if their voltages are different. That’s why watt-hours are better for comparing systems. Example of our Victron LFP-12.8/300 packs nominal energy at 3840Wh Our selection of Lithium Batteries can be found here. The industry is headed towards rating battery power by the nominal energy voltages. Instead of seeing 12, 24 or 48 volts the industry uses 12.8, 25.6 and 51.2 volts as the nominal values for watt hour calculations. Why Watt-Hours Matter More for Off-Grid Systems Amp-hours are useful when you’re staying in one voltage (most van systems are 12V), but watt-hours let you: Compare batteries of different voltages (12V, 24V, 48V). Calculate your daily power needs accurately. Match your battery capacity to your solar panel output and appliance usage. If you only look at amp-hours, you might undersize your system and run out of battery faster than you expect. How to Calculate Your Daily Power Needs Before buying batteries, figure out how much energy you use in a typical day.Here’s how: Step 1: List your appliances.Write down every device you’ll use: fridge, lights, fan, water pump, laptop, etc. Step 2: Find the wattage.Look for a sticker on the device, the manual, or search online. If it only lists amps, use: Watts = Volts × Amps Step 3: Multiply by hours used per day.This gives you watt-hours for that device. Step 4: Add everything up.That’s your daily total watt-hours. Example Daily Usage Table: Appliance Watts Hours/Day Daily Wh 12V fridge 50 8 400 LED lights 20 4 80 Vent fan 30 5 150 Air Conditioner 600 5 3000 Phone charging 10 2 20 Total — — 3650Wh Step 5: Add a safety margin.Cloudy days, inverter inefficiencies, and battery aging happen. Add 20–30% to be safe: 3650Wh × 1.25 ≈ 4,562.5 Wh/day needed. Converting Between Ah and Wh If you already know one measurement, here’s the cheat sheet: Ah = Wh ÷ Volts Wh = Ah × Volts Example: You need 4,562.5Wh per day. With a 12V system: Ah = 4,562.5 ÷ 12 ≈ 381Ah So you’d want at least a 460Ah lithium battery bank (lithium batteries can use most of their capacity, however manufactures only recommend 80% depth of discharge or less; lead-acid can only use about 50%). With your daily Wh usage calculated, remember you must have a charging source that is capable of replenishing the used energy each day too. This can be from solar, dcdc chargers, 2nd alternator, shore power or generator. Common Mistakes to Avoid Comparing Ah without checking voltage.A 100Ah 12V battery is not the same as a 100Ah 24V battery. Forgetting inverter losses.Converting 12V DC to 120V AC loses ~10–15% of energy. Only planning for sunny days.Always size for your worst-case scenario. Not tracking usage.A battery monitor like a Victron SmartShunt helps you see real-world consumption. Final Tips for DIY Van Builders Always start with watt-hours when planning your system. Use efficient appliances — LED lights, efficient DC fridges, and laptops instead of power-hungry desktops. If you can, test your system before hitting the road. Remember: you can always add more solar panels later, but battery capacity is harder to upgrade in a cramped van. Conclusion:Understanding watt-hours vs. amp-hours is one of the most important steps in building a reliable off-grid van electrical system. Once you get the hang of converting between them, you can size your battery bank, solar array, and charging system with confidence — and keep your lights on and fridge cold, no matter where the road takes you. If you need assistance putting together your electrical system, please call 754-444-8704 an agent at Vanlife Outfitters will provide their expertise in the perfect electrical system for your application.
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