I have a Class A motor home considered to be a 50 amp service. It has a Victron MultiPlus-II 12/3000/120-50 2x120V inverter/charger. It has the Cerbo, some solar, lithium batteries and various Victron/lynx supporting equipment. I have a question about Power Assist. I read the manual and dig into the forums and get two different descriptions for what Power Assist does.
- Power Assist will supply additional power for sudden power draws such as the kick required when an air conditioner starts up. This is a short time boost and the wattage will return to the rated source power. It is primarily designed to prevent blowing a breaker. This is how the guy who installed it described it to me and what the manual seems to describe.
- Or, Power Assist will pass through the AC source power and then will add power from the batteries should you exceed the AC source amperage. This would be a long term boost that will last as long as the batteries. For a 30 amp power pedestal source I would have the 30 amps from the pedestal plus another 25 amps (3000 watts at 120 volts) from the inverter. I’ve seen discussions in the forums and a couple of You Tube videos that present this description.
My system seems to be working as a short term boost (#1). The forum discussions talk about “turning on the Power Boost.” I’ve dug through the manuals, the discussions, and the Cerbo menus and haven’t found a description or button for turning on Power Assist. The closest thing I find is, Power Assist is an automatic function that you don’t need to manage. At most you may need to set the AC Current Limit to match your power source amperage.
At 50 Amps I have all the power I need and don’t need Power Assist. At 30 amps I may have need for Power Assist, either the short term (#1) or long term (#2). So, which is it, a short term boost as described above in #1 or a long term boost as described in #2?
So far as setting the AC Current Limit, should I set it at 30 amps when hooked to a 30 Amp pedestal, or should I set it a couple amps lower, say 28 amps, as a cushion to reduce the risk of blowing the pedestal breaker?