Description

Battery Combiner is a microprocessor-controlled, voltage-sensitive relay used in dual-battery and split-charge systems to link a starter battery and an auxiliary battery automatically.

It monitors charging voltage and connects the two batteries in parallel once one reaches the preset charge threshold, then isolates them again when the voltage falls to the discharge level, so the auxiliary battery charges from the alternator without drawing down the starter battery. Operation is bi-directional, allowing the starter battery to be replenished when the auxiliary side is charged from a mains charger. Rated for 12V and 24V systems at 120A.

As a relay-based combiner it introduces virtually no voltage drop, unlike a diode isolator. An emergency parallel-connect function allows the two batteries to be linked manually to assist starting from a discharged battery.