need help with generator

[itchyfeet]

smooth sailing until generator hookup,
here is what i've got, vfx 2812 x 2, (hooked up in series/parallel stack) flexmax 80 x 2, psx auto 240 trans, mate2 , hub4, 380ah 6vlt x 16. sharp solar tiles x 32. champion 7500 gen wired to both (IN) legs in ac panel.
I get a hum in both inverters and redlight error (solid red) i've gone over my wiring multiple times and cant figure out the problem, dc and ac works fine, it throws the error with generator off but wired, when unwired system works correct again. input breakers, bypass breakers, hot legs in 1 and 2, hot legs out 1 and 2 seem to be wired correct.
can anyone help?
Thanks

[Cariboocoot]

Welcome to the forum.
You say series/parallel - as per Page 27 in the manual?
First inverter designated as "master" and second as "slave" (HUB ports 1 and 2 respectively). First inverter using black AC line for input and output (and autotransformer) and second using red AC line.
Now, without the generator connected the two inverters function off batteries and supply 240 VAC up to 2800 Watts?
Or is the master inverter only functioning with the slave never turning on?

Next, check the output lines from the generator. That model does not have a neutral-ground bond built in. This bond should only occur at the final AC out from the transformer, feeding the service panel.

If the gen wiring is disconnected at the gen does it work? Or only if disconnected at the inverter inputs?

It sounds as though the generator wiring is picking up AC hot from one inverter side and feeding it into the other. Try disconnecting the autotransformer and seeing if the problem persists (no loads, no generator running - just wiring).

[Cariboocoot]

Link to wiring diagram that includes the autotransformer: http://www.outbackpower.com/pdf/wiri...1-00_REV_A.pdf

[itchyfeet]

[Thanks for the reply, yes to pg 27, slave assignment and hub assignment,slave has blinking green light which i think is good, with ( gen unplugged) and input breakers on, both inverters have flashing yellow light waiting for ac which i also believe is good, but it does sound like cross wiring, I wired system from ps2 ac and ps2 dc diagrams, system is very close except instead of dual output and dual bypass breakers i used single breakers x 2 of each could this be the issue ? it seems strange that with everything hooked up, it faults by just plugging in the genn that is not even running. thanks again for info, i will give it another shot in the morning.]

[Cariboocoot]

Particularly check to make sure there is a neutral-ground bond. Otherwise the neutral can become "hot" and back-feed through the gen windings causing the inverters to see a low AC in Voltage.

[Ralph Day]

Not sure if this is pertinent but I had the neutral from my T240 autotransformer end up carrying current when gen charging. Not OB but Xantrex stuff. The L1 and L2 were not balanced, one leg showed full current expected, one leg very little current measured...the remainder was carried back to the genset via the neutral. This didn't affect my 10kw genset but made my 5kw genset act very unbalanced. By isolating the neutral and just feeding 240vac to the autotransformer the problem dissapeared and things functioned properly.

Just wondering why is there an autotransformer in the mix when there's 2 inverters putting out 240vac.

Ralph

[Cariboocoot]

Not sure if this is pertinent but I had the neutral from my T240 autotransformer end up carrying current when gen charging. Not OB but Xantrex stuff. The L1 and L2 were not balanced, one leg showed full current expected, one leg very little current measured...the remainder was carried back to the genset via the neutral. This didn't affect my 10kw genset but made my 5kw genset act very unbalanced. By isolating the neutral and just feeding 240vac to the autotransformer the problem dissapeared and things functioned properly.

Just wondering why is there an autotransformer in the mix when there's 2 inverters putting out 240vac.

Ralph

Ralph;

It's an Outback thing.
The autotransformer allow the two inverters to supply either 2800 Watts on 240 VAC or 5600 Watts on either leg of 120 VAC. There's other ways to arrange them; Outback has a lot of wiring diagrams to go with the many possible configurations.

[itchyfeet]

Thanks for all the help everyone, Ive been in wire chaos for the last few days, as for the added psx 240 I was told was good for balancing / getting more out of the pair of inverters, I am much closer, I now have everything running smooth except I must shut off the 240 trans when the gen is running or I end up with 480, This wouldnt be such a big thing, except that will defeat any chance of auto gen with the atkinson gscm. I spent alot of time searching for a gen with auto choke, I didnt see the purpose of auto gen if you have a manual choke, but I am back to sqaure one with that.

Not sure if this is pertinent but I had the neutral from my T240 autotransformer end up carrying current when gen charging. Not OB but Xantrex stuff. The L1 and L2 were not balanced, one leg showed full current expected, one leg very little current measured...the remainder was carried back to the genset via the neutral. This didn't affect my 10kw genset but made my 5kw genset act very unbalanced. By isolating the neutral and just feeding 240vac to the autotransformer the problem dissapeared and things functioned properly.

Just wondering why is there an autotransformer in the mix when there's 2 inverters putting out 240vac.

Ralph

[RCinFLA]

I know the Outback diagram is showing the auto transformer on output for balancing the 120 v loads but many autotransformers and just about all isolation transformers are are not 1:1 turns ratio. The are typically 1:1.02 to 1:1.05 beween the two winding. This is done to make up the transformer loss. This would upset the balance slightly when trying to do load balancing.

You might check the open circuit (unloaded, with temporary floating neutral on transformer) voltages between the two windings to see if it is equal.

[mike95490]

If you are seeing 480Vac, you have something out of phase, is my first guess.

Consider having your genset just power a charger for the battery bank, not wired into the AC mains, if you can't get it working any other way.