question

Not sure what you mean by line voltage. Hope this helps.

Multiplus looks at battery voltage to decide whether to invert or not. Battery voltage and solar output voltage are effectively identical.

Solar will provide power once sufficient illumination on panels. If battery voltage rises above 13.3V, multiplus will start inverting, allowing the dehumidifier to work. This continues until bettery voltage drops to 13V. Depending on output of solar Vs dehumidifier power needs battery may or may not get much charge. I suspect the dehumidifier will run mostly during the day/early evening.

Not sure how long the boat is being stored, but LiFePO4 batteries need to reach 100% charge to balance the cells. Plan for this as you're going to run them at the low end of the charge range pretty much continuously, internal imbalance will happen and may be enough to cause them to cut out and they might not be rechargeable by solar.

So what I think I hear you saying is this is a bad idea if I can't get it to 100% SOC after letting it drop to 30%.

Hi @Mward

More elegance preferred..

Hows about wiring your dehumidifier to ACOut2 and switching it with Assistants, using SOC (and/or V). That way you could run between two high SOC points and essentially just use excess solar for the load. Batts always well charged, and you could even add in a time delay to allow for batt balancing.

I don't have ACout2 hooked up right now and I have 4 days to get the boat ready. I live about 2000 miles from where it's going to be stored so I can't easily be on hand if there are problems. This is a good idea though. I will probably just take all the soft stuff to climate controlled storage for hurricane season and figure it out next time around. Thank you for taking the time to help me understand this.