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I've been doing research online to try to help me narrow down things. Here's what I've got:

  1. I bought a small (3500W) generator with a floating neutral. It has a 120v 3wire TT30 receptacle. No special GCFI protection built in. My intent is to power some circuits in the house when the power goes out occasionally. Refrigerator, few lights, TV, etc.
  2. I installed a new breaker in my home's main breaker panel to be used as a backfeed breaker. I installed the proper interlock kit that matches up with Square D make/model of my panel and breaker.
  3. I installed a L5-30 receptacle near the home panel and wired white to the neutral bar, black to the backfeed breaker, and green to the ground bar. This is the generator power inlet.
  4. I made a TT30/L5-30 plug to plug cable so I can connect power from the generator to the inlet mentioned above.
  5. Double checked all my wiring and everything is lined up as it should.

The result: I switch off the city power and bring up my generator system. Lots of stuff in the house works...except the circuits with GCFI outlets OR those on the few GFCI breakers that are installed.

From my reading, I believe my problem is that in my home, the neutral and ground are bonded (per code) inside the home breaker panel. Some of the current is bleeding into the home's ground system, being detected, and the GCFI's are doing what they're designed to do which is turn off.

I've read about installing a whole second transfer switch, instead of using the backfeed breaker. Cost and these are limited in circuits you can power.

I've read about setting up a sub panel to switch the neutrals. This sounds a lot like a home-made transfer switch. I might not understand this option well.

I don't want to take GCFI's out of the home circuits, so that's off the table.

Is there some smart/safe/easy way to debond the home's ground+neutral lines when I'm using the generator? One extra big bonding switch I can add in the panel?

What are all these other people with backfeed breakers doing? Seems like I'm missing something. Thanks for your help in advance.

Update - Found a clue, or maybe the whole issue! While looking at the wiring again I realized that I only powered one side of my backfeed breaker. My generator is 1ph 120v. The hot wire I put to the upper terminal so I realize now I'm only powering one side of the load center. Let's call it A since it's in the upper most position. All my unresponsive circuits are on the B side. I feel a little dumb now but I spotted that. Photo for clarity:Snapshot inside panel, with lables

So here's the question now...move my important breakers to the A side so they're all powered OR gang/bond the two terminals on the backfeed breaker. I think moving the breakers is probably safer long term.

Found this related discussion HERE.

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    What make/model is your generator? Commented Aug 22, 2021 at 3:52
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    Those hokey 6/8/10 circuit transfer switches don't work with GFCI or AFCI breakers at all. I'm not sure what your backfeed issue is exactly, but it's solvable. Did you connect the generator neutral to system neutral? Gen ground to system ground? Commented Aug 22, 2021 at 6:16
  • How certain are you that your breaker panel really does have neutral & ground bonded (as they should be)? How certain are you that your generator does not have neutral & ground bonded?
    – brhans
    Commented Aug 22, 2021 at 13:32
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    It’s a Champion open frame inverter generator, model #100574. I read it it’s manual/specs that’s it’s floating neutral.
    – magicsmoke
    Commented Aug 22, 2021 at 13:41
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    Do you have any cases where two 120V circuits share the same neutral (multi-wire branch circuits)? Commented Aug 22, 2021 at 17:03

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I installed a L5-30 receptacle near the home panel and wired white to the neutral bar, black to the backfeed breaker, and green to the ground bar. This is the generator power inlet.

An inlet has prongs sticking out of it, not socket slots. This is what you should be installing:

enter image description here

I made a TT30/L5-30 plug to plug cable so I can connect power from the generator to the inlet mentioned above.

You mean a plug to socket cable, i.e. that can plug into itself, like any normal extension cord.

Only a "suicide cord" has prongs on both ends.

I've read about installing a whole second transfer switch, instead of using the backfeed breaker. Cost and these are limited in circuits you can power.

Those things are hokey and play very badly with AFCIs, GFCIs and MWBCs. They won't fix a thing.

While looking at the wiring again I realized that I only powered one side of my backfeed breaker. So here's the question now...move my important breakers to the A side so they're all powered OR gang/bond the two terminals on the backfeed breaker.

Depends. As the article you found stated, you must search the system for Multi-Wire Branch Circuits (MWBCs) aka shared neutral. If the wiring is done in cables, the red flag will be red wires on breakers. Investigate every red wire. If it goes to a 120/240V appliance like a range or dryer, that is not a MWBC.

If any MWBCs are present, you cannot split the 120V supply to feed both legs of the breaker. You can rearrange, but you must be careful not to mis-position any MWBCs. All of them need to have handle-ties anyway, and those will ensure correct phasing. (one hot on each phase).

If your panel has no MWBCs, feel free to split and power both hot legs.

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  • Yes I made a suicide cable. Let’s put that aside for the moment. I’ll spot check the GCFI wiring around the house. I agree I don’t want to be trying to debond the home’s neural-ground.
    – magicsmoke
    Commented Aug 22, 2021 at 13:28
  • I looked at the wiring of my GFCI breakers. The white (lower/silver) and black (upper/bronze) are correct. The white pigtail is attached to the ground bar but like I mentioned above, the ground and neutral are properly bonded. I used the test buttons (breakers and a handful of outlets) and everything trips and resets as expected.
    – magicsmoke
    Commented Aug 22, 2021 at 15:31
  • I made an edit to my question above and added info about my backfeed breaker. This could be the whole problem. Wasn't powering the other side of the load panel. Now to resolve that...
    – magicsmoke
    Commented Aug 22, 2021 at 17:06
  • OK I see your edit, it's just a case that the GFCIs were on the wrong phase. Solved that. Whether you can split the gen output and feed both legs depends on if you have any MWBCs. Commented Aug 22, 2021 at 18:39

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