The Electrical System

The electrical system on any remote touring vehicle is really what makes or breaks things when it comes to ‘ease of usability’ and ‘enjoyment’. Although I wanted to keep the electrics simple on this truck, it really wasn’t that simple and it took a lot of hours to complete. A touring 4WD electrical system needs to be robust and connections need to be solid so that everything holds up to the large doses of heavy vibration caused by the often endless corrugations. In other words, you just want it to work when it should.

I wanted it done properly from the start this time and done so that all my needs were met. Although my camping ethos is minimalistic, I also wanted to know that there was room for extra things later if I needed to expand the system. I didn’t want a system of tacked-on extra bits with wires running in places that I didn’t know about or couldn’t trace.

This was also one of the reasons I bit the bullet and bought a new truck for the first time in my life. I didn’t want someone else’s legacies. Although I have a rudimentary knowledge of 12V electrics and did most of the wiring in my old Patrol, I decided that this was a job for a pro. Shane, the canopy fabricator, put me onto Aaron Cobavie from Cobavie’s Auto Electrics and together we designed the system around my anticipated needs.

Aux calcium battery

In the end, I decided the system would be based on three batteries. One being the crank battery and then two house (auxiliary) batteries. One of these would be under the bonnet and the other would be beneath the floor of the canopy.

The aux battery under the bonnet would also have the task of jump-starting the crank battery if I ever ended up with a flat in the middle of nowhere. This is currently handled via an in-cab momentary switch that paralleled the batteries through the Voltage Sensitive Relay (VSR) to allow the jump start. However, I may change this to a manual switch with a constant duty solenoid to allow the batteries to remain paralleled if needed. For instance, in the off-chance of a the notorious alternator failure after an encounter with too much mud. If that were to occur, I could in theory parallel the batteries and continue driving for some time. It’s debatable and I need to think it through a bit more still.

final configuration
final configuration

I ended up putting a single 120A/hr Deep Cycle Full River AGM battery under the canopy tray and a 97A/hr AC Delco Calcium Hybrid battery beneath the bonnet. The calcium hybrid battery was selected, as it should handle the under-bonnet temperatures better than AGM, yet still have a decent capacity to run a second fridge.

The rear auxiliary battery would receive a charge from the alternator via the REDARC Battery Management System, which would also feed in solar charge and monitor all draw. Basically, this battery would handle the rear fridge, all the camp lighting, the USB charge points, the cigarette lighter socket and the 12V water pump.

The REDARC unit and monitor, plus the system isolator and switches were all mounted on the front wall of the canopy beside the fridge where they would be protected from various knocks or damage, yet were low enough for the kids to reach them.

compressor and 12V water pump with shower head
compressor and water pump with shower head

The lighting consisted of two white LED strips, one on each side mounted up under the gull-wing doors, and a red LED strip that was set just inside the canopy on the passenger’s side to provide low-level illumination without attracting bugs. Both lights on the passenger’s side were fitted with illuminated touch-sensitive dimmers and the fused switch panel was also illuminated for ease of use at night.

dimmable white strip light
dimmable white strip light

We also fitted up two Lightforce ROK9 LED’s facing rearwards to aid the reverse lights when retrieving the boat at night, closing gates or reversing into a tight campsite. These throw out a broad light that isn’t so bright you can’t look in that direction and they are a very handy addition.

The under-bonnet aux battery was wired to receive the charge from the alternator via a VSR. Plus, if camped for a while, I could flick a switch in the canopy and direct solar charge from the roof to a REDARC Solar Regulator to top up power as required. The solar setup could basically feed either the Battery Management System in the back or the voltage regulator for the front battery.

For solar, Shane managed to fit two 120W solar panels on the roof of the canopy, so I should have sufficient capacity to manage my usage as long as I get a few hours of good sunlight each day while camped. An added bonus of fitting the solar panels on the canopy roof was that the air gap beneath the panels provided insulation from the sun’s direct heat, thus noticeably keeping the interior of the canopy cooler.

interior red anti-bug light
interior red anti-bug light

I’ve been asked a few times now as to why I opted to fix the panels instead of using portables and “chasing the sun” for more efficient solar collection. Well, I basically can’t be bothered with that option. Call me lazy, but for the percentage of energy I would miss out on versus the weight off my mind of having to think about it every 20 minutes, I think I’m in front. Besides that, if you use portables and face them to the sun, then forget about them, chances are you only got a couple of hours, which is basically nothing. Horizontal mounting is another one of those compromises, but it suits me fine.

Back to the electrical system.

A fuse block was mounted off the under-bonnet aux battery and handled power to the iCom UHF and my 15-year-old Recaro Driver’s seat, which still works like a charm. Fused 8 B&S cabling was also fed into the cab to the side panel on the passenger’s side behind the rear seats to insulated positive and negative lugs. These lugs serve as a power source for a small 350 W Victron Inverter, that lives beneath the rear seat and is used to charge camera batteries and the laptop mostly, plus a 50 Amp Anderson Plug for a second fridge on the back seat.

Reverse lights and twin cameras
Reverse lighting and cameras

As the canopy was not see-through, the rear-view mirror suddenly became a bit superfluous. I decided to mount twin reverse cameras up high in the middle of the back of the canopy and feed these to a monitor that clipped onto the mirror. To date, I am still uncertain if I like this arrangement, as it does restrict the forward vision slightly.

What I do like, though, is being able to turn on the camera when driving normally and being able to see out the back again. The wide-angle camera is connected to reverse and comes on automatically whenever reverse is engaged. If the monitor is on, the system then switches to a narrower view when the gearbox is in any other position.

The power-hungry ARB twin air compressor in the back toolbox was fed from the crank battery via 8 B&S cables. With a draw of around 60 Amps when under load, running the engine makes sense when pumping up tyres with this thing, but it is efficient enough for me not to bother fitting up a reservoir tank at this stage.

Next Part: The 79 Series Dual Cab Build (Part IV) – Finishing Touches

Previous Part: The 79 Series Dual Cab build (Part II) – The Canopy.

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