Victron Solar Connection to Passenger Seat Leisure Battery OK?

1Pearman · 2025-06-09T09:11:00+0100

Hi, having fitted my own solar setup to my previous vans (not Cali's) and reading up on how it should be done for the T6.1 Ocean i've fitted a Victron 100-20 MPPT under the front passenger seat with the positive going to one of the leisure battery terminal connections, and the negative going to the chassis side of the battery monitor (I drilled a hole for the connection bolt through the large silver part between the earth cable and the battery monitor). I'm then going to route the solar cables under the van into the engine bay for a plug connection in there for a portable solar panel setup. I tried it out quickly at the weekend and found it charge fine and whilst the Cali display showed a positive AMP input, the 'hours remaining' seemed strange and went from >60h to something like 6h when i connected the panel up. I think this also turned my fridge off to protect the batteries because I noticed it was off later in the day when i went to get some food out. Just wondered if there's anything wrong with how i've connected it or if anyones seen the display do this before? Most people go to the rear battery but because I want the connection in the engine bay I've used the front one.
Thanks

dspuk · 2025-06-09T10:09:36+0100

Shouldn't make a difference. The one to watch is more amps in rather than hours remaining which is based on draw vs battery levels at that exact point in time and AFAIK nothing to do with your solar setup but managed and calculated by the VW software.

1Pearman · 2025-06-09T11:27:44+0100

Thanks @dspuk that good to know. The only issue with the hours remaining is that I think it was this that shut my fridge down because it wanted to conserve battery? Can't think what else would have turned it off as it's never happened before. Strange that this would go down to 6hrs from >60hrs when i plugged the solar panel in and was getting a couple of Amps charge showing as positive Amps on the display.

Ruddster · 2025-06-09T12:41:14+0100

Excuse my ignorance but why shouldn't you wire the solar charge unit (MPPT) to both battery terminals?

WelshGas · 2025-06-09T12:47:00+0100

Ruddster said:
Excuse my ignorance but why shouldn't you wire the solar charge unit (MPPT) to both battery terminals?

On the T6.1 the Leisure Battery/ Batteries are monitored by a Battery Monitor module wired between the Battery -tve terminal and Chassis Earth.
Therefore the Solar -tve should be wired to the Chassis Earth NOT the battery -tve as this would bypass the Battery Monitor and confuse the Control Panel