Switching AC In (from Generator) to Charge Batteries

[JoeH]

I have a problem with the AC In from the back up generator, we rarely use the generator but with the coming winter I want to make sure all systems are good. When I start the generator the inverter system begins to switch over from battery to AC, but very quickly the circuit breaker trips, this circuit breaker is part of the Transformer/transfer Switch module, please see the attached pictures. I believe this module (not sure of the official description?) is bad. Is there any test that I can do to confirm this? The other attached picture is of the neutral wires attached to the buss bar you will see that there is some smoking on the wires.

Can someone identify this part for replacement? The picture is what I can see with the Flexware cover off.

This is an older installation and it worked fine in the past, since upgrading the batteries we do not need the back up power much, but I want the system to work as designed.

Thank you very much for any advice someone can offer.

Joe

[raysun]

That looks like some "original" Outback kit. I honestly have no clue as to whether replacement parts are still lurking in the dusty corner of someone's warehouse out there.
Since the system is not connected to grid AC input, why would an external transfer switch be necessary for generator input?
A transformer is not typically associated with a transfer switch, do you know its purpose in this design? I don't know if Outback had isolation transformers in their catalog back then, but did have autotransformers which could serve different configurations (and burn neutrals on occasion.)
Are the 4 inverters configured for 120/240V split phase?
Is the generator 120V or 240V output?
What is the generator brand and model?

Can you post a picture showing the internals in a single image?
Can you post a picture of the flexware chassis external view?
Is there a legend on the chassis listing XW-240, FW-X240, PS-X240, or the like?

[JoeH]

Thank you for your response, I will gather the information to answer your questions and send asap.

Thanks again

[raysun]

I'm guessing here.

FW-X240 ALAutotransformer wired for generator voltage step-up. Two FX class inverters are shown. Two more would be wired in parallel with those.

The 4 inverters are connected series/parallel to output standard 120/240V split phase power that is fed to the house load panel.
The generator outputs 120VAC.
The device between them is an Outback PSX-240 Autotransformer wired to step the generator voltage up to 240VAC to feed the inverters.
There is no transfer switch in the PSX-240, rather each of the inverters has an internal transfer switch that activates in sync as AC input is detected.

Second possibility:

In this design the four FX inverters are connected as two groups of two inverters.
The generator is 240VAC output.
The inverter cluster output is 240VAC split phase. It is fed to the PSX-240 Autotransformer for load balancing.

There are two other possibilities (Outback was busy creating variations) described in the Hub 10.3 Quick Start Guide:
https://old.outbackpower.com/downloads/ ... _start.pdf

[JoeH]

Hi,

Thank you for the feedback.

The second wiring diagram is what we have. The picture files I have seem to be to large to upload, same as the others...?

From your original response:
Are the 4 inverters configured for 120/240V split phase? Yes
Is the generator 120V or 240V output? 240V

How can we determine if the Outback PSX-240 Autotransformer is/has failed?

Is there a drop in replacement model for the part (FW-X240) that we have now? Also, do new systems still utilize this design?

Thank you,

Joe

[raysun]

Well. Outback's forum just logged me out and vaporized my response.
I'll not duplicate it any time soon.

In a nutshell:
PSX-240 looks to be on the market for a staggering $1000+
There is no definitive home test to determine if the unit in place is healthy or house-fire bound. The smoked neutrals lean toward the latter.
Is this architecture still in use? Yes. I use equipment with the same low frequency inverter design but 2 decades advanced development and deployed the same capabilities at less than half the cost at current market prices for Outback equivalent capacity.

[JoeH]

Thank you for your assistance, having this feedback is helpful, definitely gives food for thought.

cheers

[raysun]

Is this system the main source of electricity for your house, or a backup?

[JoeH]

Sorry to miss your question...
The system is out primary power supply to everything, house, shop, wells, etc. truly off the grid. The generator is a back up or if we have a big load.

We did recently discover what we believe to be the problem, we learned that the generator is wired as a 120/208 set up. There is a schematic to reposition the wiring to make it 120/240, we have not done so yet, but we think that will do the trick.

I will let you know.

Thanks again for your assistance.

[raysun]

Great news! That configuration would certainly cause an issue.