The reference build
A 1990 camper that has crossed the country twice
Everything we sell was worked out on this unit first — a 20-foot, single-axle 1990 Kit Monterey, stripped and rebuilt around a Victron lithium system. It is not a showpiece. It is the truck that proved the specification.
Power and storage
The bank, the inverter, the solar controllers and the monitoring were specified as one system rather than bolted on a piece at a time. That is the single biggest difference between this and a factory coach: nothing here was sized to hit a sticker price.
- Storage
- LiFePO₄ house bank with integrated BMS
- Inversion
- Victron inverter/charger
- Charging
- Shore, solar and DC-DC from the tow vehicle alternator
- Monitoring
- Victron Cerbo GX with VRM remote monitoring
- Architecture
- 12 V — see the honest note below
Solar
Enough to run the working day without starting anything. The array layout matters as much as the wattage — panels shaded by an air conditioner or a satellite dish are panels you paid for and do not have.
- Array
- 1.1 kW rooftop
- Controllers
- Victron MPPT
- Penetrations
- Sealed and inspected at every roof entry
Connectivity
Two years of working out of this thing established the actual requirement: the connection has to come up when the unit does, without someone climbing on the roof.
- Satellite
- Starlink, mounted and powered from the DC system
- Network
- Local router, wired to the system rather than a wall wart
Site capability
Levelling, shade and light are what turn a parked trailer into somewhere you can actually work. The lighting is zone-switched so you can light the work area without lighting the bedroom window.
- Levelling
- Four-point electric
- Awning
- Electric
- Lighting
- Zone-switched exterior LED work lighting
Four-season tank system
This system is being fitted now, and the photography is being taken as it goes, because once the belly armour closes none of it can be photographed again without taking it apart.
- Status
- In progress
- Heating
- Thermostatic pads bonded to the tank shells
- Lines
- Heat tape under the insulation, not over it
- Underbelly
- Rigid foam, then riveted aluminium armour with weep points
What we would do differently — and tell you to do
Naming the weaknesses first is cheaper than being caught on them, so here is the honest list on our own build.
| On the prototype | What we specify now |
|---|---|
| 12 V architecture | 48 V on anything built to order. A 3 kW inverter at 12 V pulls roughly 250 A continuously, which means parallel 4/0 cable and 400 A Class T protection. The same load at 48 V is about 63 A on 2 AWG. The cable alone pays for the change. |
| Improvised wiring in places | Every circuit labelled at both ends, a printed panel legend, and an as-built schedule handed over with the unit. The prototype is being brought up to that standard now, which is exactly the work we sell. |
| Built to a budget, in a hurry | Built like a house with an axle under it. RV manufacturers build to a weight and price target, and that is why their systems fail first at the tanks and the panel. |