As part of our Renault Master campervan conversion, we needed to address battery charging.
We have quite a large 290ah AGM battery, so we need to get juice into it. We have three ways to get power:
- From the alternator/engine when running
- From a mains hook-up
- From a solar panel on the roof
It is possible to get independent devices to manage battery charging from each of these devices, however we wanted to simplify the setup so we opted for a triple charger. This single unit connects to the alternator, the solar panel and the mains, and coordinates all three to effectively charge the battery.
We use a Votronic VBCS 12V Triple Charger (45A DC-to-DC, 30A Mains, 350W solar). There are a few different models depending upon the size of your battery. Each model outputs a slightly different current, so with bigger batteries you’ll want a Votronic with a higher output (smaller will work, it may just take a while to charge the battery).
Wiring is fairly simple:
- Solar panel. Both positive and negative feeds from the solar panel are input.
- Mains. This has a 3 pin input plug (much light you’d find on a desktop computer). We have a standard 13 amp plug connected to this, which in turn we plug into the 230v socket we have in the van (connected to the mains hook-up)
- Engine/Alternator positive feed. This connects to the positive of the main starter battery (ours actually runs underneath the van and up through the floor)
- Positive and Negative leisure battery. Straight forward.
There are three additional cables that we ran:
- Temperature sensor. This is connected to the + terminal of our lesiure battery.
- Ignition feed. This is needed to tell the charger that the ignition is on (so as not to drain the starter battery). Ideally this would be connected directly to the alternator, but we didn’t want to mess with that so it’s just ignition connected. The cable doesnt actually carry charge, it’s just used as a signal.
- An additional neg (starter battery) to neg (leisure battery). Not strictly necessary as the van chassis acts as the earth. However, it’s good to have for high current draws. Ours runs underneath the van again.
Ours votronic is mounted flat on the floor of the van. There are four screw holes, one at each corner.
We also have the remote display to monitor what’s going on. Given our mounting on the floor this is very handy as the LEDs on the device are hard to see. The remote also has some handy functionality, such as lowering the mains charge current if you’re at a site with a poor power supply. The display uses a single cable to connect to the main charging unit.
When connected to the mains the fan on device spins up emitting a small noise, however it’s very quiet and has not interrupted our sleep.
We’ve used this all through the summer and it’s been a good reliable device.
The Amazon links below have more details and enable you to see the different models each with different charge output.
Amazon UK link: https://amzn.to/2JwDqzN
Amazon Germany link: https://amzn.to/38OvsdV



