2nd Battery & Split Charge

The ambulance came with 3 batteries and 2 split charges (a factory-fit one of unknown status, and a posh 3-battery MOSFET unit). Two were under the seat, one was floating free in the back. We removed everything and then reinstated a single battery under the seat, so we now needed to reinstall a 2nd battery to run the “house”:

Battery cradle from 25×25 angle:

A couple of tabs to bolt to existing holes in the outriggers:

And a cutoff switch tucked under:

Fusebox under the sink, as there's a hole in the floor at the back where a cable used to come in, so it comes straight up behind the fridge - we ran twin ~16mmsq from the 2nd battery up to a marine fusebox:

Wiring to starter battery & split-charge in progress:

Lovely, all tucked neatly away (or so I thought): The 2nd battery is wired to the two MOD battery posts under the seat which link to the original ambulance systems (fuse panel in passenger footwell), supplying the interior lights, night heater, etc. - there's a maxi-fuse in line to catch any wiring faults downstream of the split-charge.

eBay £1.99 Chinese panel volt meter sits nicely in the fusebox lid - we disconnected it at night because of the glow:

As it turns out, the fancy 3-way split charge thing that came with the ambulance (purchased by previous owner) just didn't want to play, no idea why not (yes, I even read the manual!). Possibly it needs all 3 batteries connected or something. Whatever, by this stage we didn't have time for mucking about so I picked up a 140A smart split-charge relay from Furneaux for ~£35, quick & easy to fit, does the job.