XW6048 Load Imbalance

n4wff

I have my XW6048 running, and was wondering about plugging my 30A, 120v RV into it. With the A/C running, the load will be around 2400W or 20A on 120v. The manual states the maximum load on each leg is 37.5A and the maximum imbalance between the legs is 75%. If I am only running the RV from the inverter, one leg will have all the load, and the other leg will have nothing. Does the 75% rule apply in this situation, or will I be OK?

BB.

Re: XW6048 Load Imbalance

As I understand, with only one phase loaded:

37.5 * 0.75 max loading = 28.125 amps maximum draw

There are other ways around the problem (such as using an auto-transformer to "balance" XW load to 240 VAC, and give you 120 VAC output.

Or, if you only need 120 VAC, reconfigure the XW internal transformer wiring to 120 VAC only and change to 120 VAC firmware (as I understand).

-Bill

Joe_B

Re: XW6048 Load Imbalance

I have had a greater than 75% imbalance on mine a lot and it does not seem to be an issue, try it and see what happens, the XW has good fault protection so nothing bad will happen other than the inverter throwing a fault.

n4wff

Re: XW6048 Load Imbalance

Thanks, that is what I wanted to hear. As long as all it will do is throw a fault, I will try it. I didn't want to let the smoke out. I called tech support and all they would do was read page A2 of the manual to me. Not much help at all.

Joe_B

Re: XW6048 Load Imbalance

When I installed mine, I did make a few changes in my wiring in an attempt to at least balance some of the loads but for example in the morning, I run a 110V microwave and the rest of the house is essentially off. This makes my load imbalance almost 100% and I have never thrown a fault because of it but, I will put in the caveat that when I have this condition, it is only about a quarter of my capacity. I would be cautious about doing it near the max capacity of the inverter.

ChrisOlson

Re: XW6048 Load Imbalance

The XW can handle a pretty large leg imbalance. And the inverter itself is under-rated compared to most on the market. So they'll handle a pretty big overload for quite awhile before complaining about it. But when you run the inverter imbalanced you also lose quite a bit of efficiency. So if it's a continuous draw thing like this camper, I would highly recommend installing an autotransformer on your PDP to balance it. We have a Outback PSX-240 on ours and it greatly enhances the efficiency of the system with leg imbalances, as well as allowing true full-load operation of the inverter without exceeding the rated continuous output on either L1 or L2.

As you can see from this photo we still get some leg imbalance even with the transformer. But without the transformer the leg imbalance with the load shown in this photo would've been over 20 amps difference, which would've overloaded the inverter. With the transformer it handles the load with no problem at all.

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Chris

Joe_B

Re: XW6048 Load Imbalance

I Dont even follow my own advice, This morning while I was cooking, I had 24.9 amps on L1 and 2.9 amps on L2 and there were no issues. So I guess my system will handle a very imbalanced load with no squawking. I will add that I am grid tied and the inverter was not supplying 100% of the load at the time.

HTH, Joe