Hi
I have a 30amp fused shore power already installed in my van. Can I use this with the Multiplus-ii? Or do I have to swap my shore power to 50amp? I purchased the Multiplus-ii already because i got a really good deal on it. I'm hoping there's a setting I can change or it will run fine with the 30amp.
I'm not planning on having a heavy load on the system, maybe a small microwave at most and a laptop.
400ah of battery
This is my first van and experience with this equipment.
thanks
There is a setting for the input current limit.
Please read the manual.
Assuming you're in North America:
30A shore is 120VAC single phase.
50A shore is 120/240VAC split phase.
Most victrons sold in the states are 120VAC only. They do not make a split phase model, but they make a 2x120 model that intelligently manages switching back and forth between 30A and 50A shore power supplying power to both legs of a 50A RV AC panel. I'm assuming you have the pure single phase model. In that case you MUST only supply 120V to the unit. An adapter to plug 30A RV power cable into 50A shore only pulls from one 120V leg, so you're good there.
There are two important values:
1) AC input limit - the maximum amount you can draw from shore and not trip input breakers.
2) Battery charge current - maximum charge current sent to the battery.
Must remember that the two currents are NOT at the same voltage. 30A input current limit is 30A * 120V = 3600W. 3600W / 12V = 300A of battery charging current.
Also important to understand the AC input current limit is for BOTH charging AND passing through AC to any loads you're using, i.e., loads + charging. The unit will manage the charge current to stay under the AC input limit, but if your loads exceed the AC input limit, you can trip the breaker UNLESS you have PowerAssist enabled where the inverter will draw from batteries and boost AC output to meet the loads in excess of the AC input current limit.
For a 400Ah battery, you likely want to limit it to 40-80A charging for longevity.
No reason to upgrade your shore power connection. The 3000 VA Multi produces 2400 watts while inverting or about 20 amps @ 120 volts. Charging is 120 amps or about 14 amps at 120 volts from shore power.
Set the input current limit to 30 amps and the Multi will adjust charging current so that the combined charger draw and AC loads will remain under 30 amps.
