#DUAL BATTERY ISOLATOR WIRING DIAGRAM INSTALL#

The VSR terminals are at the same potential as the positive terminals on your batteries and the system is grounded to the chassis. I have also found heater hose and ‘pond tubing’ useful for protecting cables.

Split corrugated tubing to protect the cables.

Extra ring terminals for the heavy gauge cables.

I bought some cheap red car audio cable on ebay and taped the ends black for negative. Car audio cables can be cheaper but they have softer insulation. Large gauge battery cables can be very expensive. A simple component but prices vary considerably. I reckon you can buy all the components separately and save.

I did not use the three battery terminals in the Projecta kit.

#DUAL BATTERY ISOLATOR WIRING DIAGRAM INSTALL#

There were insufficient terminal lugs to install the fuses.No fuses and fuse holders were supplied.4 m of red battery cable was supplied.That was not a good purchase as several items were not adequate, not included or not required: Dual-sense VSRs monitor both batteries and will allow charging the main battery from the aux side. Single-sense VSRs monitor only the main battery. This allows starting the engine with the aux battery if the main is flat. Some VSRs can be operated with a manual override, else a manual switch can be connected in parallel with the VSR. A VSR should always keep the starting battery charged. Switch the engine off and the VSR will disconnect the aux battery. A VSR will connect the aux battery when charging voltage is sensed at the main battery.

VSRs are popular for several good reasons: high current capacity, automatic connect/disconnect and simple installation.

Wiring diagram for dual-battery system with Voltage Sensitive Relay isolator.

Dual battery isolator wiring diagram