DX3 air conditioner wiring question

[mookieblaylock]

I've got the coach connected to a 20A circuit in my garage to keep the batteries charged. With very little on other than the residential fridge/freezer, the control panel shows the coach pulling around 3 - 4A. It's getting hot down here, so, while working in there the last couple of nights, I decided to try to turn on the forward AC unit. It came on fine, cooled fine, and, while running, the control panel never showed more than 11 - 12A. All good.

What I found strange, though, is that when the compressor first kicks on, the inverter switches from 'AC In/Charge' to 'Inverter On' for about 30 seconds. I thought that the AC units were wired direct to shore power and/or the generator, and, as such, would have no bearing on the inverter whatsoever...they'd either have enough input current to turn on, or they wouldn't. However, it seems that the system is actually kicking over to house batteries to find enough current to spin up the compressor.

Can someone help me understand what exactly is happening in this case? For what it's worth, I do have the inverter input setting changed to reflect the 20A circuit it's connected to.

Thanks!
JT

[KRedburn]

I believe the input setting on the inverter is for load sharing. Ifyou set it to 20amp then the inverter/converter thinks it can use up to 20amp for battery charging.


when I have mine plugged in at home to a 20 amp outlet just to get loaded and frig running I set inverter/converter to 5 amp. I have successfully run 1 ac without it switching to invert and using batteries. You said it was only momentarily switching which I think is the compressor and fan startup surge which is brief. Once running it "backsoff" so there is sufficient amps to run ac and charge batteries.

Sounds like your system is working correctly. Try changing the share to 5 amp.

Ken

[mookieblaylock]

Thanks, Ken.

It definitely appears to be working fine; I guess I was just shocked to see it flip over to the inverter momentarily for compressor/fan startup. Until I saw this, I was under the impression that the AC units had no access to the inverter/house batteries....that they were wired in directly to an A/C source (shore power or generator).

[KRedburn]

MB one other thing.

Make sure that your extension cord is a heavy duty one 12 gauge wire minimum. Many cords are made of 14 gauge or even 16 gauge wire.d

the inverter does a passthrough when it sees genny or shore power. During compressor start it may be seeing a voltage sag thus causing the switch over.

[mookieblaylock]

I've got it plugged in using the coach's shore cord and an adapter...no extension cord in use.

[jkoenig24]

I paid extra for 10A extension cords. Better safe than sorry.