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I will soon be purchasing a 15K watt, 50A generator and an exterior 200A on/off/on transfer switch. Nothing is an issues except for connecting generator to transfer switch cabinet. Must a male/female connection be used or may the generator connecting wire be permanently connected to the transfer switch? The male plug end of the connector wire would remain and be used on the generator end.


The generator is expected to be a Pulsar 15,000W Dual Fuel Propane/Gasoline Portable Generator. The transfer switch will be Emergency Power Transfer Switch 200 Amp Non Fused Double Throw Surface. The connector wire will be RV Extension Cord Generator Cord 15ft 50 Amp Power Cable 6/3+8/1 Copper Wire.

The house has hot water base board heat operated via an outside wood burning stove. Also have a propane fired furnace in the basement. Usually the basement furnace is not used. Well pump, too.

The propane use will cut the available watts to about 10K. That's alright, as my wife and I added up all the possible items that would be used and we come out to bout 75% of available watts. That's if everything runs at once. Not likely. Presently we use a 5KW generator and, while it provides us with what we need, it's all very basic and we do a severe limit on what's used.

Not to mention there's a bit of effort involved in making sure the main is off and so on. Fine if I'm home. But I want this to be easy and safe for anybody else to use. So, yes, the whole house will be able to be operated, as it now selectively is.

So, may that female end of the power cord be directly connected to the transfer switch as will be the input line from the meter? If it's necessary to install a male shielded plug, I will, but...it does introduce another connection that I see is not necessary.

  • Are you trying to transfer your whole house here, or are you putting in a standby subpanel so you can only transfer a subset of your house's loads to the generator? Also, how is your house heated/cooled, and what make/model of generator set do you have your eyes on? Finally, is that transfer switch you are buying a 2-pole or a 3-pole switch? – ThreePhaseEel Apr 17 at 2:32
  • Can you get us a make and model number for the switch you're planning to use for this please? – ThreePhaseEel Apr 17 at 3:32
  • Please use the edit link underneath your question if you want to update it with additional information. – Niall C. Apr 17 at 3:43
  • so you're asking if the connecting cable for the generator is allowed to be permanently connected to the transfer switch? – Jasen Apr 17 at 5:14
  • Is your main breaker outside at the electric meter, or inside with the rest of your breakers? – ThreePhaseEel Apr 18 at 0:25
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Can a 15kw generator be hard wired eliminating the male female connection at the house. Yes a generator can be hard wired but you then cannot use the cordage you planned to use. When hard wired they are usually in conduit and a junction box switches to flexible conduit for the last few feet to absorb the vibrations.

A 15kw generator can be connected by a cord through your transfer switch or lockout device. However you will need to use a power inlet to feed the transfer switch.

The power inlet has male prongs and connects to a standard female cord cap of the same type. How is this legal? The male prongs are isolated by the transfer switch or lockout device so they only have power from the cord of the generator. They are never live from the house feed. This is normal for portable generators because hard wire would be required if there is no plug in device.

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Bad news: given a typical portable generator, you'd have the wrong switch for the job

While your intentions with the transfer switch you are looking at are noble, your plans, like many well-intended but underinformed generator transfer setups, would not normally quite reach the point of Code compliance. In particular, while your plan treats the hots correctly (the most important part for not zapping linesmen), your proposed setup would run aground where neutral and ground meet if you used it with a garden-variety portable generator. In particular, your main panel has the neutral-to-ground bond in it, which is a critical component of your house's electrical system. However, most generators also have a neutral-to-ground bond in them, as well, so that they can be safely and legally used as stand-alone power sources, say on a jobsite or somewhere else utility power is unavailable.

As a result, if you hooked up everything as you are currently planning it with a typical generator, you'd have a case of dueling neutral-to-ground bonds, sending stray currents in undesired directions and possibly even tripping the GFCIs protecting the high-power outlets on some generators. There are two ways to fix this: one is to pull the bond out of the generator, but this renders it unusable for portable work, and very few generator manufacturers these days provide instructions for removing and reinstalling the bonding straps on their products. The other, normally less problematic way is to get a transfer switch that switches both the hots and the neutral. This way, your house wiring is only connected to one neutral-ground bond at any given time, whether it be the house's or the generator's.

In particular, your current proposal uses a GE TC10324R double-throw, non-fusible enclosed switch with two switching poles and a solid neutral. However, if you had a bonded neutral generator, you would need a three pole switch in order to have enough poles to switch everything. GE makes one of these, the TC35324R, but it's unobtanium for us DIYers. However, Midwest makes a not-quite-equivalent switch known as the GS3262G, which is somewhat available. Furthermore, Siemens makes a full equivalent to the TC35324R in the DTNF324R (HD has it on their site, even, but it's a bit spendy).

Worse news: you're a switch would have been even more wrong for the job at hand

If we were not switching an entire house, or switching a feeder from a combination meter breaker device, we would be done here. However, since you are transferring your entire house, and likely have your main breaker fitted at your main panel instead of at your meter, we're not done here, as there are more hurdles to overcome. In particular, NEC 230.91 requires the service overcurrent protection to be in the same spot as the service disconnect:

230.91 Location. The service overcurrent device shall be an integral part of the service disconnecting means or shall be located immediately adjacent thereto. Where fuses are used as the service overcurrent device, the disconnecting means shall be located ahead of the supply side of the fuses.

This leaves you with two options if you wanted to continue down this path with a typical portable generator: either a made-for-purpose, service entrance rated, 200A manual transfer switch with a switched neutral fitted, or a fused double-throw, three-pole safety switch. This poses a problem, as the former switches generally don't have switched neutrals, and the latter are extremely expensive. (Generac discontinued the switched neutral kit for their version, and the EZ-Connect switches don't even seem to offer the option to begin with.)

Even if you could get such a switch for a reasonable price, you'd still find yourself in an installation pickle, as the aforementioned neutral-to-ground bond for your house would have to be moved from your existing main panel to the new switch. This requires replacing the service-entrance cable between the two locations with a four-wire cable, at a minimum; you may also need to extend the grounding electrode conductor to the location of the new panel, which is a challenging task as you need to use compression splices and their associated tooling for this job.

There's a better solution to the problem of standby power out there

Of course, none of this solves the problem of load-management. While it's possible to do that by manually flipping breakers on and off in your panel, there's a reason that you don't see whole-building transfer in larger buildings: it doesn't scale as load-management concerns start to predominate. Manual load selection is error-prone in the heat of a power outage, and even automatic load shed devices can pose problems if they misoperate or are misconfigured.

Instead, what people whose generators actually matter do is take the time up-front to determine which loads and circuits are important enough to belong on the generator, then move those loads to a subpanel that is switched between the normal and standby power sources. This approach means that non-critical loads (like the dryer) can't disrupt critical loads (like the well pump), at the cost of not being able to have the dryer, in this example, on generator power at all. It also means that you can use a smaller, less-expensive transfer switch, and don't have to worry about relocating the service disconnect and its associated neutral-to-ground bond to the transfer switch, for that matter.

The simplest way to do this for most generators, albeit not yours, would be to use an integrated switching neutral manual transfer switch and standby subpanel; Reliance Controls makes such a thing in the form of their Panel/Link X series, and certain Eaton CHGEN panels have this feature as well. (It's also possible to kit out certain main-lug QO panels as such a thing, but it takes a bit more work.) If none of the aforementioned are an option, one could use a three-pole, double throw, non-fused switch and an ordinary main lug subpanel instead.

Fortunately, with your generator, since it has a floating neutral, you can dispense with some of that complexity, and use a more normal manual transfer switch with a solid neutral, or even a pair of interlocked breakers in a bog-standard subpanel with the standby loads fed from that new subpanel.

Of course, you'll need to provide a four-wire feed from the main panel to the transfer switch, with neutral and ground separated and the neutral/ground bond removed/not fitted at the subpanel. This approach also generally lends itself better to using a separate inlet box and transfer switch, instead of having the inlet mounted into a knockout on the transfer switch (or a generator cord and plug trailing from the transfer switch) as in your proposal.

Good news: If you really want to do whole-house manual transfer...things are actually rather simple

If, for some reason or another, the use of a standby subpanel is absolutely not an option for you, it is possible to do whole-house transfer in your situation. The good news is that you can get made-for-purpose hardware for this; the bad news is that what you have won't quite do the trick, due to the NEC 230.91 compliance issue mentioned above.

For your case, the simplest route, instead of using a separate transfer switch, would be to get the correct breaker interlock kit for your electrical panel (in your case, a HOMCGK2C), and use that to interlock the main breaker with the generator breaker. You can then run normal house wiring from the generator breaker to a generator inlet box (Reliance PB50 or equivalent) mounted on the outside of the house; from there, the generator just plugs in using a generator cordset (NEMA 14-50R to CS6364).

If you were trying to do this with a bonded neutral generator, you'd need a 200A enclosed circuit breaker device in a weatherprooof (NEMA 3R) enclosure to serve as the new exterior service disconnecting means. This goes next to your meter enclosure, with a normal 3-wire set of service-entrance wires run into it and the grounding electrode conductor extended/rerun to it as well. From there, though, you then need to run a four-wire feeder to one of the aforementioned 200A three-pole, double-throw switches (either a GS3262G, most likely, or the DTNF324R if you must), with a generator inlet fitted directly to the switch using a Reliance Controls PK50 kit. (A cord-and-plug setup for connecting the generator could be set up using the correct cord grip where it joins the permanent wiring, but some inspectors may consider such a "generator tail" outside the scope of what cordage can legally be used for.) Finally, you would need to continue that four-wire feeder run from the transfer switch to the existing interior panel, removing the bonding means at that panel while you're at it since it's now going to be a subpanel.

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  • So the generator is, similar to a sub-panel, in that it should not have the neutral and ground bonded. Bonding takes place only in one location, that being the main panel. Is that correct? – mrcaptainbob Apr 18 at 18:49
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    @mrcaptainbob -- that's one way to do it, but requires farting around with your genset trying to figure out where its N-G bond is, as that's not in the genset's manual. The other approach is to leave the N-G bond in the generator and have the transfer switch switch the neutral as well as the hots, which makes it a lot easier to use any old generator, and also means you don't have to mess with modifying yours. Big question: is your main breaker out at the meter, or inside with the rest (or most of the rest) of your breakers? – ThreePhaseEel Apr 18 at 21:26
  • The main breaker is at the top of the main 200A panel inside the basement. Distance from meter is about twelve feet. Meter is the remote control type located on the outside of the house. – mrcaptainbob Apr 19 at 1:33
  • @mrcaptainbob -- who do you have for an electric utility, BTW? – ThreePhaseEel Apr 19 at 2:23
  • Consumer's Power. South Central Michigan. Jackson County. – mrcaptainbob Apr 19 at 17:17

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