Generator breaker vs. regular breaker-is there a difference?

[Lightnsound]

I went and looked at my service panel, and sure enough, it's 20A breakers all over the place, but only 15A receptacles. Of course, a 20 amp plug will have a sideways prong and won't plug into a 15A receptacle, but what would protect the system if a 15A appliance was faulty and drew 20A, overheating the receptacle? I'm surprised the NEC doesn't prevent that situation from arising.

The odd thing, or one of them, is that the duplex receptacle as a whole can handle the 20 amps, but either of the two outlets can handle 15 amps max. So it's possible to plug two 15 amp devices devices and trip the breaker, and that's only on one wiring device. Usually there are several on a single breaker.

And you are right about the line cords not being permanent and other associated points. I was just rambling a bit.

 

[CobyRupert]

...as a side note regarding 15amp recepts on 20amp ciruits, which is the norm for multi-yoke circuits I'm also pretty sure the code: NEC (NFPA 70) says that if there's only one receptacle on the circuit it has to be fully rated (i.e. 20 amps). ....and 1 duplex receptacle counts as two.

 

[IHDiesel73L]

So what would protect the 30 amp receptacle from being overloaded? As long as this generator, and future generators, has a 30 amp or less breaker on it, you're good. But why not put in a 50 amp receptacle to match the wire and panel breaker?

Wow-really didn't expect this to go 4 pages, but it's a good discussion. I don't know why I didn't think of this before, but since I have the wiring and the breaker inside to handle it I could do a 50 amp male receptacle on the house and simply make up a "custom" generator cord out of the appropriate sized cable with a 30 amp male plug on the generator end and a 50 amp female plug on the house end. Then if I ever got a generator capable of putting out 50 amps I could change the 30 amp male plug to a 50 amp male plug.

 

[joshuabardwell]

Wow-really didn't expect this to go 4 pages, but it's a good discussion. I don't know why I didn't think of this before, but since I have the wiring and the breaker inside to handle it I could do a 50 amp male receptacle on the house and simply make up a "custom" generator cord out of the appropriate sized cable with a 30 amp male plug on the generator end and a 50 amp female plug on the house end. Then if I ever got a generator capable of putting out 50 amps I could change the 30 amp male plug to a 50 amp male plug.

Whatever you do, don't use a male to male cable, also known as a suicide cord. You never want live prongs. You want a 50 amp inlet on the wall, along with a custom 30-to-50 cord. The 30 amp end would be male and plug into the generator. The 50 amp end would be female and plug into the inlet. This would also always prevent feeding the cable with a 50 amp source and overloading the 30 amp end.

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[Coyote machine]

On the prior page someone mentioned UL as certifying electrical components. They do NOT certify anything- they LIST an item and that is all they do. It's a rating system that has to be followed. They test to make sure things meet a certain standard and then LIST the item as such.

 

[crazyal]

Since you have the cable and the breaker I would get a 50 amp generator receptacle for the side of your house, garage, or where ever you plan on having your generator. Like you said, you'll have a lock out device so either the main or generator breaker can be closed but not both. You can then make a cable that can handle 30 amps with a 50 amp female to connect to the house and 30 amp male to connect to the generator. Or you could use larger cable that can handle 50 amps to future proof yourself if you ever get a larger generator.

As far as a breaker protecting just the downstream circuit, that's wrong. In the case of an AC panel the buss bars are able to handle far more power than the breaker so in that case that statement would be correct. But in the case of a generator you also need to protect the internal wiring of the generator.

 

[Lightnsound]

As far as a breaker protecting just the downstream circuit, that's wrong. In the case of an AC panel the buss bars are able to handle far more power than the breaker so in that case that statement would be correct. But in the case of a generator you also need to protect the internal wiring of the generator.

That's why the generator has a breaker on board and doesn't rely on a customer supplied over current device.

 

[duke7595]

As a homeowner you can do lots of work yourself including plumbing and electrical. It just has to be inspected by a qualified person and signed off on my the inspection agency of record. In my case it was the electrical company prior to energizing but since you obviously live in a permit zone, you may have to apply for a permit to do the work, then you can run the line, install the box and breaker but then the city or county inspector will have to sign off on the work. If you get a knowledgeable person then it may go ok if your work meets strict code requirements. My son (who is a certified electrician) once put in the main power supply lines to his house and used the correct size wire AND put it in conduit. The power company guy that came to look at it wouldn't pass it because "it has to be direct buried cable" and no amount of arguing that conduit installation is better than direct burial would convince him. Even showing him in NEC wouldn't convince him. We had to request a different guy to come inspect and of course he passed it with flying colors. Never did find out if they fired the other guy. Typically this can be the kind of person that inspects and can cause you some grief if they only know "this is the way we do it" type of action.

This is a typical event that happens all to often, and the reasoning behind it is "I won't pass it because I can mentality" as you mentioned some inspectors cause much grief and unnecessary expense to many homeowners because as stated they can. I don't know if you complained of this persons conduct but I think I would have for the sake of others he's done this to.

 

[bigdeano]

If the 8-3 cable you have is NM cable I think it's rated for 40 amps. I've always used #6 cable for 50 amp circuits. Some electrician please chime in.