Sterling Power 12V/24V to 48V DC-DC Battery Charger - 65 Amp

• Charge your 48V house battery bank from your 12V or 24V vehicle battery at up to 740W!
• Bi-directional design also enables charging from the house battery bank to the vehicle battery for maintaining the vehicle battery.
• Buck Boost design, offering high efficiency (95-98%)
• Simple installation and setup
• Current limiting charger
• Lithium safe
• Smart Alternator/Euro 6+ compatible
• Ignition feed or Vibration Sense modes can be used for turning the charger on and off.
• 6 preset battery types
• 6 self recovering protections
• Low temperature trip for Lithium Ion batteries
• Optional Remote Control available separately

Specs:

BB124865

Input voltage range: 9V-32V
Auto Detects 12V or 24V input
Input current rating: ~60A at 12V and ~30A at 24V
Output voltage range: 38-62VDC
Output current rating: 13A
Reverse current rating: 20A at 13.4V(max) & 10A at 26.8V
Continuous Rated output power: ~740W (57V @ 13A)
Continuous Rated input power: ~760W
Quiescent current: 5mA
Efficiency rating: 93-95%

Self recovering protections:
under voltage protection
input over voltage protection
output over voltage protection
over current protection
charge over temperature

Operational Temperature -20 Deg C -> 60 DegC

Approval CE | UKCA
E-Marking 24*10R06/01*3789*00
Cooling Method: Thermostatically Controlled Variable low speed fan

Dimensions 200mm x 130mm x 56mm (7.88" x 5.12" x 2.20")
Weight 1.0Kg (2.20 lbs)

This charger correctly calculates the battery's or bank of batteries' charging needs and boost charges with the right charging algorithm for your battery anytime the boat or vehicles alternator is running. It also goes into lower float voltage when the battery is full. Doesn't have the limitations of a traditional relay.

Reverse Charging Feature:

The BB124865 is able to charge in both directions. Provided there is over 13.2V on the leisure battery (13.5V if lithium) and the starter battery is below 13V the BB shall allow approximately half current to flow back to the starter battery up to about 13.4V (float voltage). It simply allows the starter battery to remain topped up when there is surplus energy in the domestic battery. This feature will NOT drain your domestic battery - it simply takes surplus. Once your alternator / engine turns on or you provide the BB with an ignition signal the BB reverts to normal charging of the leisure battery. This mode can be disabled, but is on as default.
This is ideal for allowing the starter battery to remain topped up when you have solar / wind / charger - charging up your leisure battery.

Paralleling multiple battery to battery chargers together?

There are no problems installing multiple BBs together in parallel to increase the power. For example, you can parallel a BB1240 with a BB12120 to get 160A of charge current. Likewise, two BB1270 units for 140 amps total or two BB12120 units for total of 240 amps directed to house bank charging from one alternator or two alternators as input sources is a common application.

Benefits:

1) Redundancy, having multiple DC-DC chargers can help with redundancy. If one was to get damaged, the other BB(s) shall continue charging.

2) Fine tuning the current. As each BB has 3 different power levels, adding multiple BBs together gives you 6, 9, 12 etc.. different power levels. For example, if you wanted 90A you could get a BB1270 and a BB1240 and set the power levels to 85% each via the BBR remote (to give you approximately 90A). Thus, giving you large levels of flexibility to hone in to a specific charge current.

Adjustable Current Limit:

The default current setting for the BB range is 100% - meaning that the performance default is full power. If you wish to reduce the performance of the BB, here you can set to 85% or 65% charge rate. Examples of why you may wish to reduce performance:

1) if you have solar panels and the weather is good, by reducing the power of the BB, you shall conserve fuel.

2) The alternator is better suited running at slightly lower current than what was expected or you don't want the alternator to work as hard.

3) It may be recommended by your battery supplier to charge the battery up at a slightly lower current. If one of your lithium batteries within your leisure battery bank fails, you may be exceeding the C rating of the remaining batteries.

4) future proofing. If you have installed a high powered BB, in the assumption that one day you shall put a larger alternator on and/or more batteries in your system. You can reduce the power for the immediate install and increase the performance of the unit at a later date.

Manual PDF