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I am trying to hook up Honda 7000 to a Reliance transfer switch (just using their manual at the moment). The setup requires balancing the 120 volt loads among 3 transfer switches for each side of the generator. Two switches are ganged together to get 240v for my water pump leaving only four 120v. transfer switches. It appears that 2 switches on each side can be used to balance the left and right sides of the generator (22.9 amps, 5,5K watts @ 240v is maximum total output). So there are 4 switches left to handle all the 120v appliances, receptacles etc. Each switch seems to be wired to one 120v breaker in the house panel. Unfortunately, there are NOT four 120v breakers in the house load panel that are house-wired up to all the things I would like to run.

****Additional Info: Wow. Did not expect answers so quickly. Great answers. I have not actually purchased a transfer switch yet. I downloaded a Reliance 31406CRK manual and was tracing out how it might work. I got more and more concerned that it would not work very well for me. Then i found this website. Glad I did, although it will take a while to become familiar with it.

For over 25 years I have ignored the admonition to not back feed the generator through the panel. I have clearly marked the panel to "switch the power company switch off before doing anything." Then, hook up the generator and flip the breaker for the generator. The power company has done work up here and they have seen the generator (even changed their meter) and never said anything about it. It has worked perfectly many times until last month I had to have the 3 hp water pump replaced. They put a pump saver device on it and the next time I used the generator the pump would not run. My Devilbiss 7000 generator was putting out 268v. for some reason (another problem to solve) and the pump saver said NO.. I had to turn on several "burners" on the electric range to get the generator's rpm down to lower the voltage and the water pump took off. In the mean time I bought a Honda EU7000is.

I thought, maybe with the new generator, it would be safer to have a transfer switch interlock in case someone else has to engage the system. In my internet search I did not see the interlock device of which someone sent a picture (I can't see who at the moment, but much thanks). That device would provide considerable protection against any confusion. I will have to rearrange my breakers a little, but fantastic solution.

It seems as though two people responded to my question if I am reading this right. I thank you very much for your time and thoughtful responses.

It is still not clear to me how the two 120v phases from the two halves of the generator (to make 240v) end up balancing the full power of the generator by distributing what is left from the 220v water pump to the other 120v breakers, which may be on or off depending. I am hooking a watt meter up to each leg. Maybe that will show what is going on.

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  • Why are you using one of those chintzy "select circuit" type transfer switches to begin with, even?! Can you give us an inventory of the loads/circuits you want backed up by the generator, for that matter? Dec 27 '20 at 22:37
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    Stop installing. Tell us all about your service panel (model, photo of panel and label if you can find it), and we'll see if it'll take a $60 generator interlock that'll let you switch your entire panel. That way you won't have to make painful choices, you can power any circuit you want, and better, you can send back that $300+ thing, and buy some really nice stuff with the money you get back. Generally transfer switches of that type are for obsolete panels like Zinsco or Pushmatic. Dec 27 '20 at 22:39
  • @Harper-ReinstateMonica Obviously, if you read my answer below, I agree completely. Not meaning to give the awesome Harper-ReinstateMonica guy any advice, but I'd humbly suggest to post that as an answer. Dec 27 '20 at 22:45
  • So, what 120V loads/circuits are you trying to run off the generator? Also: manual for the generator in question for anyone else who needs it Dec 28 '20 at 3:06
  • One other sidenote: according to this brochure, the EU7000is is a floating neutral generator Dec 28 '20 at 3:21
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NO, you can't do that. That would cross connect circuits which could lead to overloading the neutrals. While you haven't said, I think the type of transfer switch you have is something like the pic below.

We hate to say it here, but those aren't all that great. They are expensive and limited in capacity. Many here prefer a power inlet for the generator, wired to a breaker with a mechanical interlock with your main breaker on your main panel. The obviously vary by panel but you can get a rough idea from the 2nd pic. Taking this approach allows you to pick and choose which circuits to run off the generator by turning off or on various breakers. It's code legal and safe, convenient and not expensive.

EDIT: Thinking about this for a few more minutes, your idea is a really terrible one. You'd have cross connected circuits and the end result is to do any kind of maintenance you'd have to turn off multiple breakers to depower a circuit. PLEASE don't do this. Others have commented just now saying a mechanical interlock is best and ironically, least expensive. As 3ph said, please shoot us a pic of your main panel to better help you.

transfer switch

interlock kit

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  • Wayne, George has the photo in his answer of the “proper” way to do what you want. These interlock kits are not hard to install and you shut off the breakers you do not want to power like a electric oven or pool pump (I waited for them to come down in price before putting one in, similar to your experience). If his answer is helpful give it an up vote if you do this a green check mark helps others find the accepted answer.
    – Ed Beal
    Dec 28 '20 at 17:53
  • @EdBeal WOW! Thanks Ed. Coming from you that's high praise! At my previous home I had a split buss panel (no main breaker) so installing a mechanical interlock wasn't possible. I dk if kits like the one I posted was even available 20 years ago. The main panel was also undersized for a planned remodel, so I installed a sub-panel with a built in MTS / interlock and moved most of the circuits to it. I never really liked the split buss panel so I thought, what the heck, I'll just swap it out and installed a 40 space SquareD QO panel. Overkill, but isn't that what we do here?! LOL Dec 28 '20 at 18:15

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