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I bought a 12Kw Pulsar G12KBN portable generator with a 50Amp outlet to power my house and my 4ton AC during Louisiana storm seasons (last year we had 6 storms) and I'm looking for best recommendation on how to go about hooking it up to my house. All YouTube videos out there are pretty easy to follow but they have regular panels with Main breaker shutoff in them. (Not my case) which is why I'm struggling to find an answer.

My house has a 200A Main Panel outside with the meter combo on it and including the 100Amp breaker to the garage sub-panel which feeds my whole house, 40Amp oven breaker and 40AMp AC breaker however I have no Main disconnect, but I have 3 service disconnects.

Please advise how should I go about installing a transfer switch or do I need an interlock switch? or what do I need in my case? If you can draw a diagram that would be nice. Attached are pictures of my panels.

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My idea is to add a subpanel with a main disconnect right next to it and move just the garage subpanel and the AC into this one and disconnect it from the grid with an interlock kit. So I'd be moving the 100Amp and 40Amp breakers only and adding a 50Amp breaker from the generator receptacle. Now what rating Panel would I need? Can I get away with 100Amp panel or 150A or do I need a 200A panel connected to same rating breaker in the meter combo panel? See the drawing.

How do I wire neutrals and ground in all the panels, and what gauge wires between them?

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Morning guys, wow i'm suprised how many people are willing to help, thank you so much.

@ThreePhaseEel - i did the measurements for you and my multimeter showed that there is continuity between the neutral and ground on generator's receptacle, it was beeping showing 0.2 on the screen.

@Harper - from a little googling for outdoor panels this one came up to fit my needs and the price is good, its a a big panel even bigger than the meter combo, but i couldnt find something smaller IN STOCK :) and the reason i bought the stuff is the shortage, and i'll better buy it then take it back if not needed than wait for it for months. This was the last panel in stock at Lowes :). I dont really care about the feed through lugs. It came with it so it is what it is.

From a little research i want to mention that i will be hooking up a soft start switch to my AC and that should be sufficient to run the AC on my generator.

i'll be attaching some pics with my intended location for panel and softstart switch that i bought.

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  • What is the model number of that panel you may be able to convert it to a main breaker. Then use an interlock kit , since I can only see 1 open breaker would need at least 1 tandem to create 2 open spaces but then you could choose whatever circuits in the main, much easier than moving them all over.
    – Ed Beal
    Mar 24 at 22:44
  • What loads are you wanting to run off the generator? Mar 24 at 23:11
  • Also, can you check to see if there's continuity between the Neutral and Ground pins on your generator's 50A receptacle? Mar 24 at 23:41
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The meter panel is a "rule of 6" panel. You're on the right track: interlocking that is probably impossible so re-arranging things is a good plan. The hard part is that there are so many valid ways of doing the job it may be difficult to choose.

Your proposed idea is a good one. Not having done any demand calculations, but knowing that there isn't a huge difference in cost between 100A, 150A, and 200A main-breaker panels, I'd suggest you choose a 200A main-breaker panel. Keep in mind that's only its limit -- it's perfectly fine that you might feed it from a breaker less than 200A at the meter panel. You'll need to check the label on the meter panel to find out what types and ampacities of breakers are approved for use there. Finding a branch circuit breaker larger than 100A may prove challenging (or costly).

An alternative is to move the A/C and oven breakers into the existing subpanel. It appears to be convertible to main-breaker type by removing the two hot lugs and installing a QOM2 main breaker in the space at the top. Labeling on the panel will confirm. The panel is nearly full so you'll need to remove some of the existing breakers and use tandem or quad breakers to pack it tighter. You could then add the interlock right into this panel. There are two interlock kits for Homeline panels. From one glance it looks like HOMCGK2C is the one you would need, but of course you'll need to verify. A drawback of this approach is that the entire house would effectively sit behind a 100A main. If this existing subpanel is rated for more current you could choose the 150 or 200A main breaker for it, upgrade the feeder wiring to the meter panel, and put a larger breaker in the meter panel just as in the solution you originally proposed.

Another possibility is to replace the meter panel. Get a new meter-main which does have a main disconnect breaker, supports an interlock, and has plenty of spaces available. It is perhaps daunting, but the process goes something like this:

  1. get building permit if required in your area
  2. ask electric utility for a temporary disconnect (my utility does this at no charge)
  3. remove the old panel, install the new
  4. get work inspected
  5. ask electric utility to re-connect
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  • Thx guys for the comments and suggestoins. To answer some of the comments During a power outage i will definitely need the HVAC, the fridge and my intrenet equipment plus TV, what else to do during power outage with a 2 and a 4 year olds ? LOL.
    – Gene
    Mar 25 at 2:52
  • @Gene -- can you please take the measurement I mentioned on your generator? (i.e. checking for electrical continuity between the neutral and ground slots of the generator's receptacles?) Mar 25 at 4:11
  • Fridge, lights, internet and entertainment are trivially small loads. Any random Honda will do those for ya. Your load problem is that stupid HVAC. Mar 25 at 5:13
  • @Gene -- also, yes, can you post a photo of the nameplate on your air conditioner please? Mar 25 at 11:32
  • @Gene -- one more question: would you rather have the transfer panel inside or outside the house? Mar 25 at 23:37
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Yes, your plan of a subpanel makes the most sense. I would install it directly beneath the meter-main if it can fit there; otherwise immediately to its right, and I'd use EMT or Rigid metal conduit to connect them. These provide a valid grounding path and remove the need to run a ground wire. Do not use PVC no matter how much more comfortable you are with it.

I would buy a very particular main breaker panel. You're looking for a 200A panel for which the manufacturer offers a generator interlock which is stocked. Right now there are lots of interlocks that are in the catalog but not findable anywhere because of COVID related demand.

Obviously, you fit the interlock to the subpanel and do the normal thing.

I couldn't care less about HOMeline compatibility, HOMeline is "exactly what it says on the tin", and Square D deliberately under-supports it to punish you for not overpaying for their industrial "QO" line. Not a fan :) On the upside, they do make a 200A branch circuit breaker.


Running out of breaker panel spaces is a great frustration and annoyance, so you should take steps to prevent that by buying loads of extra spaces. Spaces are cheap. And notably, your existing 30-space panel is full, and it hardly has any 240V breakers, so I can tell you're barely loading it, and have never tripped that 100A breaker.

One of the breakers in the new panel will be a 100A breaker feeding your existing 30-space panel. If the wires could support it, you could upsize the breaker to say, 125A, or even use thru-lugs (giving 200A)... but I really don't see a point, since you're not overloading it now, and it's full.

That panel you initially bought is a thru-lug panel. If that's where you're going with that, it makes sense, but again that panel is full, so I don't see where that's going to go.

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You'll need to take that panel back and get the correct transfer panel for your generator, or else you have dueling banjos bonding screws in your house

The panel you purchased, unfortunately, isn't as useful as you think it is, because in Homeline, like most other breaker lines, you can't use their interlock kits with a bonded neutral generator like yours. This is because there can be only one place neutral and ground come together in your electrical system, but the breakers (interlocked or otherwise) only break the hot wires when switched off, not the neutral.

As a result of having your meter-main's and your generator's neutral/ground bonds in parallel, you'd get wayward current taking alternate paths to get back to where it came from whenever you had the generator plugged in (not even running, just plugged in), which is a NEC violation (see 250.6), potentially dangerous (due to unexpected current on grounding paths), and potentially highly annoying (your AFCI breakers may not like unexpected neutral currents, and will express their displeasure by falsely tripping).

Preventing this, though, is fairly simple at this point. You'll need to take that "mobile home panel" you bought at Lowe's back and order in a switching neutral transfer panel instead. Unfortunately, though, your options are pretty limited here: the Reliance Controls XRH/XRK series panels and a few Eaton CHGEN...SN panels are about all there is out there for this task. Given that you're using Homeline breakers, and want to mount the transfer switch outdoors, I'd recommend the former, with an XRH0605DR providing a relatively low-cost option, while the XRK versions of that panel can be used if you want more expansion "wiggle room".

As to the remaining parts, you'll need a Reliance PK50 inlet kit, as well as a short conduit nipple, 1" in diameter with matching locknuts, some 6AWG THHN (two blacks, one white), and a HOM260 for the utility connection, as well as some NM cable of ordinary (14 and 12AWG) size appropriate for rerouting whatever's going to the generator, as well as ½" NM clamps for that cable, and various sized wirenuts to make connections with.

Lifting the generator's bond

If you would rather do generator surgery than order a switching neutral transfer panel in, that is an option, though. You'll need the panel you recently acquired, a Reliance PK50 inlet kit to provide a place to plug the generator into, some 6AWG THHN (black/white/green) to connect the inlet to the generator breaker, a HOM250 for said generator breaker, a HOMRBGK2C generator interlock kit to keep the generator from backfeeding the grid, a PK15GTA grounding bar for your new panel, a 2" RMC nipple and matching locknuts to connect the new panel to your existing main, some 1AWG Al XHHW-2 wire to make connections, a knockout plug/blank of the correct size for the existing A/C flex KO in the meter main, and a few CuxAl insulated mechanical splices suitable for said 1AWG wire, as well as an inch-pound torque wrench and corresponding torque screwdriver to tighten things down with.

The first step in installing this is to prepare the new panel, starting with the PK15GTA grounding bar. After that, the HOM250 goes in the top right spot, then the HOMRBGK2C interlock is fitted to the panel as per the instructions. With that done, the PK50 inlet kit can then be fitted to the right-side or bottom center KOs on the panel and wired up to its breaker with the 6AWG THHN, while a KO of the appropriate size at the bottom right is opened for the A/C whip to get moved to, and the KO on the left side of the panel is opened up and fitted with the 2" nipple using a locknut on the inside and outside. With that done, two sets of 1AWG Al conductors (hot, hot, neutral) are run from the lugs (main breaker lugs, neutral lugs, feed through lugs) on the new panel out the nipple, creating a 12" "tail" on the main breaker set and a 3-6" "tail" on the feed-through lug set for wiring inside the meter-main. Finally, on the "feed through lug" and one of the neutral lug tails, the mechanical splices get pre-attached, and a locknut is landed on the exposed threads of the nipple so that it'll be outside the meter-main once everything is together.

Remember to use your torque wrench and/or torque screwdriver to tighten the connection setscrews on breaker, panel, and connector lugs/bars to the manufacturer's specified/marked tightening torques! You'll also want to scrape paint off around the knockout on the inside left side of the panel so that the locknut can establish grounding continuity, then touch the paint job up when you're done.

Now, you can install and mount the new transfer box you just built up. You'll want to schedule a power outage with your utility to do this (just call their customer service and ask, most will do it for free during business hours) so you don't have to work around hot busbars in your meter-main. Once the outage starts, you can then knock out the right-hand knockout on the meter-main so that the 2" nipple will fit into it, and disconnect the hot and neutral wires from the 100A feeder breaker and upper neutral lug. With that out of the way, you can then deal with pulling out the 40A breaker for the air conditioning and disconnecting its wires, as well as the green ground for the air conditioner whip.

Once you plug the open KO in the bottom of the meter-main where the A/C whip once went, you can then move the 40A breaker to a suitable spot in the new transfer panel. With that out of the way, we then can fit said panel where you have proposed, with the "tails" and nipple fitting into the meter-main via the KO on the right, and the panel mounted in a suitable fashion for your brick walls.

Once the transfer panel is in place, it's time to wire it up to the meter-main. First, the paint around the KO for the nipple gets scraped off, then the last of the 2" locknuts goes into place to attach said nipple to the meter-main. Once the nipple's taken care of, and the paint touched up carefully (no painting conductor ends, lugs, or busbars!), you can then proceed to remove the conductors from the 100A breaker in the meter-main + the upper neutral lug and connect them to the corresponding connectors on your tails. With that done, the "tail" ends that don't have the connectors on them are then terminated on the 100A breaker and the upper neutral lugs, completing the wiring inside the meter-main. Of course, you'll want to use your torque wrench and/or torque screwdriver for making these connections!

You can now button the meter-main back up and have your utility turn your power back on, as reattaching the A/C can be completed in the transfer box with the 100A breaker that now feeds it turned off. Once the whip's conduit connector is attached to the new panel, the green wire in that whip goes to the ground bar you pre-fitted to the transfer panel, and the two black wires land on the 40A breaker that you moved over. Once again, the torque screwdriver will be needed here so that you torque the lugs on the breaker and grounding bar correctly.

With all that out of the way, you can button the transfer panel up, turn the 100A breaker on, and proceed to remove the bond on your generator. Last but not least, you'll need to label the generator as having a floating neutral in addition to adding the NEC 702.7(C) floating neutral (non-separately-derived system) verbiage to the labeling on your transfer panel.

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  • I may add a diagram later (me and sloppy-paint-diagrams aren't exactly the best of friends) Mar 25 at 23:36
  • thank you for more information on this, now i see your point, however can you check this guys video at 5:35 minutes in the video with a generator just like mine he explains how to disconnect the neutral and ground and let me know if i can do the same thing and keep this panel youtube.com/watch?v=Lm9Cu2tXUXo
    – Gene
    Mar 26 at 16:12
  • @Gene -- disconnecting the bond on a generator means you need to replace that bond, one way or another ,if you want to use the generator for portable power Mar 27 at 0:28
  • i'm planning to attach this generator to the house semi-permanent, meaning i will only use it to power my house and nothing else, i will also convert it to NG but this is another project, right now my only concern is to do the electrical work correctly, so i can be prepared for this season. Clarify something for me, if i remove the bond on the generator then i must have the bond in the panel that i'm planning on installing, is that right? so lets say if somehow i disconnect the bond from the meter combo during outage i have to bond it in the new subpanel..am i correct?
    – Gene
    Mar 27 at 16:14
  • @Gene -- the meter combo's bond is a permanent factory bond that you aren't going to be able to remove without wrecking the thing. If you remove the bond in the generator, then you only have to switch the hots Mar 27 at 16:56

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