I have a Multiplus 24/3000/50 installed on a sailing barge. We live aboard and spend most of the time connected to shore power on our mooring, but go off sailing for a few weeks every year. I have recently installed a 400 watt solar panel and 2 x 280 amp Lifepo domestic batteries. When connected to shore power the Multiplus keeps the batteries fully charged, so the solar panel does not contribute anything, but if I turn off the Multiplus we have no mains supply. Ideally I would like a direct connection the shore power, but still be able to switch on the Multiplus if the solar panel doesn’t keep up with demand. Is there a way to achieve this?
Yes. One way is by programming your Multiplus with VE-Configure via a computer and a MK3 dongle.
From Memory, the last settings tab is called “systain, using other energy sources”? Here you can specify a voltage that the mains power will charge the battery up to, and the solar charger will keep the battery topped up.
The default victron lithium float setting is 27volts, you can set this to say 26.5volts and the shore power will charge to that voltage. The solar will the top the battery up. Depending on what voltage you set, this means the shorepower will keep the battery charge to say 80% and the solar will top it up to 100%.
The other way is that I’m sure there are also settings in Victron Connect to tell the charger to turn on below a percentage or voltage, say 30%. and then turn off at sat 60%. the solar can then take care of the rest. This is also normally programmed via a computer and MK3 dongle.
Thanks for this. The downside of this approach would be that when we are cruising and want to charge the batteries from the generator, we would need to reset the the configuration to be able to charge the batteries to 100%.