Off-Grid Van Conversion

A self-built campervan inspired by the farm

→ Alternator Charger

Mfg. / Part #: Sterling B2B1260 Tags: battery, electrical, solar

The B2B1260 alternator charger is a DC-DC converter that takes the varying voltages from the main car battery and converts it to the proper voltage for the batteries, depending on their state of charge. It can provide a maximum of 60A which also protects the alternator from overheating and overcurrent.

The alternator output voltage on modern vehicles can swing widely, due to regenerative braking and other electronics controls, so is not suitable for charging a battery bank (especially ones that require tightly controlled charging profiles).

The B2B is needed since on modern cars the output voltage of the alternator/starter battery can vary widely due to regenerative braking amongst other things. The converter makes sure the voltage is at the right level to charge the batteries as well as using the right charging profile for the Lithium batteries.

alternator charger

(See full resolution image of the system at DWG-02-BATTERY-COMPARTMENT)

Ford alternator specifications:


Full-size PDF CAD diagrams of the system can be found below:

  • DWG-01-AC-SYSTEM(shows the inverter/charger and the shore power hookup)
  • DWG-02-BATTERY-COMPARTMENT (shows the connections in the main electrical battery compartment and also the solar and alternator charger systems)
  • DWG-03-12V-SYSTEM (shows the 12V distribution fuse block, branch circuits, and loads)

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