Growatt 3000 lvm - unable to set shore power amp limit for a limited shore power connection

[Light24bulbs]

I've just installed a growWatt 3000 LVM. This is replacing my many individual boxes.

One big issue with my setup, however, is that my shore power is pretty limited. It's on a long run and it's only a 20 amp circuit. I can't really pull more than 1,500 or tops 1,800 watts out of it before voltage drop becomes excessive.

Most of the time, that's no trouble, but once in a while I'm doing too many things at once. What I really need is for the system to switch back over to battery power in that case. It's even worse if the unit is also charging the battery at the same time. So far I've simply set the charge current very low to help.

Now, if the shore voltage gets pulled TOO low, it will switch back to battery momentary, and then it will cycle between shore and battery continuously about once a second as it repeatedly pulls the shore power too far down. This sucks and is going to wear something out.

Does anyone know of a way to accomplish a programmable limit? Is this something the MPP all-in-ones can do but the growatt can't? I would gladly switch if so, I can still return this.

Thank you

 

[Casteil]

I bumped into that with my initial testing. It really depends how you intend to use the unit. If you're going to use it for solar, you could probably have it in "SBU" (Solar > Battery > Utility) mode so that it only ever uses utility power as a last resort (i.e. your solar/battery are depleted, so it'll switch over to pass utility power through to your loads).

FWIW, I have not found a way to set a limit on this unit's draw on shore power. I don't think it's possible.

 

[Light24bulbs]

Yeah I thought about doing that but unfortunately there's not enough solar here in the winter to really make that viable. It'll be on shore power most of the time.

I think I'm just going to run proper lines. I ran 12 guage when I did this and put in standard 15a outlets to my rv power hookup.

I will shorten the run and and use 8 guage wire and a full 30a service.

As it is I'm losing about 35% of my power to line losses just pulling 1.2kw. That's a waste.

 

[Casteil]

Yeah I thought about doing that but unfortunately there's not enough solar here in the winter to really make that viable. It'll be on shore power most of the time.

I think I'm just going to run proper lines. I ran 12 guage when I did this and put in standard outlets to my rv power hookup.

I will shorten the run and and use 8 guage wire and a full 30a service.

As it is I'm losing about 35% of my power to line losses just pulling 1.2kw. That's a waste.

Yep.. that's a pretty big deal and something I'm going to have to be conscious of too.

I think I've settled on using some L5-30 hookups for 120V 30A both ways (shore power out to the cargo trailer with my solar setup, then an inlet to feed power from the trailer into my generator transfer switch) I'm probably looking at around a 40-50ft run one-way.