Dual battery system added

I’ve been a bit worried about drawing down the started battery using the Engel fridge constantly. The standard FJ Cruiser battery is about 75 Amp hours, which means at a draw of about 2.5A, the fridge will kill the battery completely in 30 hours or render it unable to start the car in about 15 hours.

So after doing some research I found the Redarc (Redarc Website) voltage sensitive relay to control the draw down of the starter battery and enable charging of both when the car is running.

I bought a battery mounting kit (Off road downunder 4wd accessories) and the Redarc SBI12, moved the power steering pump with some additional pipe work and then wired the batteries together.

This picture shows the position where I mounted the battery before. The next few pics show the relocation of the power steering reservoir and the mounting of the battery box.

The positive cable runs in front of the radiator and is 2 B&S size in a corrugated conduit about 1.38m long. The negative is 480mm to the body behind the battery box. The positive from the starter battery to the SBI12 is about 380mm long. The SBI12 is mounted horizontally next to the starter battery.

The finished installation came up really neat, although I did buy a plastic clamp as the one supplied in the kit interferes with the battery box. (Making one out of a piece of right angle steel would have been tidier)

After the battery installation, I ran a new circuit from the auxiliary battery to a switch inside the car and then to a power outlet for the fridge as well as a double USB outlet.