Portable Generators Proper Hookup

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Around here, chicken houses seem to be a source of dangerous wiring, a friend of mine bought two, and wanted me to put in transfer switches so he could use his tractor powered generator. One house had a 30 amp two pole breaker feeding a dryer outlet where they would use a suicide cord, the other was the same way, except instead of a breaker, they lugged the wires under the line side of the main!
 
jumper said:
What about 408.36(D) for a back fed breaker using an interlock kit?

(D) Back-Fed Devices. Plug-in-type overcurrent protection
devices or plug-in type main lug assemblies that are
backfed and used to terminate field-installed ungrounded
supply conductors shall be secured in place by an additional
fastener that requires other than a pull to release the
device from the mounting means on the panel.
Click to expand...

I've added that to my list. Even if a few things are not required does anyone disagree that the components on the list will all make for a code compliant installation?

1- Breaker interlock between main and backfed CB's
2- Listed inlet box
3- Properly sized backfed CB and conductors.
4- Listed power cord
5- Breaker Fastener
6- Sign at service equipment
 
Funny how, even after three 'generator' articles, the NEC never really addresses what most folks want to do. To me, the key word is "portable."

Now, when Weather System "Chicken Little" causes the lights to go out, folks are not going to run to Harbor Freight and tow off a massive trailer-mounted genny. Nope; they're going the grab that $500 'cube' off the shelf and hope it fits in the trunk of their car. THAT's a 'portable' genny.

IMO, there's only one proper way to use such a genny: with extension cords. IMO, they ought not be tied into your permanent wiring in any manner. No need for a ground rod, no risk of back-feeding the grid, no need for a 'suicide cord.'

Refinements? OK.... a scaled-down 'spider box' with 'normal' receptacles and a built-in light. Maybe make a little 'doggie door' in the wall for the cords to pass through.

If you can't live with cords, then you need a REAL genny.
 
renosteinke said:
Funny how, even after three 'generator' articles, the NEC never really addresses what most folks want to do. To me, the key word is "portable."

Now, when Weather System "Chicken Little" causes the lights to go out, folks are not going to run to Harbor Freight and tow off a massive trailer-mounted genny. Nope; they're going the grab that $500 'cube' off the shelf and hope it fits in the trunk of their car. THAT's a 'portable' genny.

IMO, there's only one proper way to use such a genny: with extension cords. IMO, they ought not be tied into your permanent wiring in any manner. No need for a ground rod, no risk of back-feeding the grid, no need for a 'suicide cord.'

Refinements? OK.... a scaled-down 'spider box' with 'normal' receptacles and a built-in light. Maybe make a little 'doggie door' in the wall for the cords to pass through.

If you can't live with cords, then you need a REAL genny.
Click to expand...

Well, you're absolutely correct but in the real world ppl are not going to install doggie doors, build spider boxes, drag a bunch of ext. cords all through out the house just to be code compliant. PPL want quick and easy, especially the ones who lose power several times a year, they want something their wife can handle when a power outage happens while hubby is at work or out of town earning a living. Can your toddler run his/her walker across the cords on the family room? I see suicide cords on most portable generator set ups which is dangerous; so if an interlock kit can be a safer install and make an affordable portable generator more user friendly than I'm all for it. Maybe the code needs to get up to speed with the rest of us.
 
unfortunately, the codes are not oriented around the needs of the average homeowner. they are oriented around the needs of the people who make up the code panels and they usually have a profit making interest in there somewhere.

most homeoners will never have a generator, so there is little incentive to deal with the relative few who do in some rational way, so the homeowners with a portable 2kW generator get sandwiched in with a plant that has a 500 kW permenanlty installed generator.

one would think there would be some way make this a whole lot easier on homeowners.

one of the issues is that one cannot even use extension cords temporarily to hook up things like furances and water heaters since they are inexplicably required to be hard wired. if they were just plugged in like any other appliance, one could run a cord to them during a power outage.

it seems to me that the cheapest answer involves a female to male cordset set to connect up to the generator and a back to back outlet wired from outside to inside of the house with a male receptacle on the outside and multiple regular female outlets on the inside. this would serve to allow roughly a 5 kW generator to be used and still be under 20A. you still need some way to plug in stuff that is normally required to be hard wired like furnaces.

there actually are some single pole transfer switches sold exactly for this purpose, but they get to be a little pricey when a 50 cent outlet and $5 cord would work every bit as well and be just as safe. it turns out though that in a fair number of localities, common sense has won out over code and a lot of furnaces and water heaters are often hooked up via a cord and plug arrangement.
 
infinity said:
OK, so since the storm last week I have spoken to dozens of portable genny owners and not one of them has hooked them up in a code compliant manner. If they ask what they've done wrong, most don't, I try to give them the minimum requirements required by the NEC Here's an outline what I consider to be the minimum requirements. Feel free to comment or add something that I've missed.

1- Breaker interlock between main and backfed CB's
2- Listed inlet box
3- Properly sized backfed CB and conductors.
4- Listed power cord
Click to expand...

I dont think I would suggest any of the minimum requirements you have listed above, since it does not represent the full requirements of attaching a generator to an electrical system.

Your best bet would be not to advise on it at all.
The only thing you can confidently defend the installation of , is something that you did the work on yourself.

Unless the dozens of Portable Generator owners you contacted understand the Electrical aspects prior to the generated power
getting to the panel, and have made those corrections, its more than likely that none of these suggestions would make it Code Compliant.
 
I think the GFI requirement on newer generators is an attempt to keep the homeowner from doing bad things with their generator, suicide cords will not work with them because of the service bond providing an alternate path for the neutral current if the generator bond is intact.
 
infinity said:
I've added that to my list. Even if a few things are not required does anyone disagree that the components on the list will all make for a code compliant installation?

1- Breaker interlock between main and backfed CB's
2- Listed inlet box
3- Properly sized backfed CB and conductors.
4- Listed power cord
5- Breaker Fastener
6- Sign at service equipment
Click to expand...

Technically you also need a service rated disconnect outside for the listed inlet box.
225.31 Means shall be provided for disconnecting all ungrounded cond. that supply or pass through a building or structure.
And 235.36 says it must be service service rated
 
Steviechia2 said:
Technically you also need a service rated disconnect outside for the listed inlet box.
225.31 Means shall be provided for disconnecting all ungrounded cond. that supply or pass through a building or structure.
And 235.36 says it must be service service rated
Click to expand...

That requirement is for optional standby generators. The OP is speaking of portable gen sets and the cord and plug is ok.
 
RUWired said:
That requirement is for optional standby generators. The OP is speaking of portable gen sets and the cord and plug is ok.
Click to expand...

702.1 Scope. The systems covered by this article consist of those
that are permanently installed in their entirety, including prime movers, and
those that are arranged for a connection to a premises wiring system from a
portable alternate power supply.
 
RUWired said:
That requirement is for optional standby generators. The OP is speaking of portable gen sets and the cord and plug is ok.
Click to expand...
<br><br>702.1 Scope. The systems covered by this article consist of those <br>that are permanently installed in their entirety, including prime movers,<u> and <br>those that are arranged for a connection to a premises wiring system from a <br><font size="2"><strong>portable </strong></font>alternate power supply.  </u>
 
Thanks for the heads up. I did not know that. So then all the listed inlet boxes really don't work to the code unless a rated disconnect is used inline with the inlet box.
 
RUWired said:
Thanks for the heads up. I did not know that. So then all the listed inlet boxes really don't work to the code unless a rated disconnect is used inline with the inlet box.
Click to expand...

According to everything I am hearing at all the IAEI meetings I have attended for the past year of so the portable generators that come with the receptacles as part of the generator can be connect to a building only as a SDS. This is outlined in FTCN of the UL White Book.

Now comes all those who are going to point out that not all generators are UL listed but here in NC it is a violation to connect anything to a building that is not listed.
 
jap said:
I dont think I would suggest any of the minimum requirements you have listed above, since it does not represent the full requirements of attaching a generator to an electrical system.

Your best bet would be not to advise on it at all.
The only thing you can confidently defend the installation of , is something that you did the work on yourself.

Unless the dozens of Portable Generator owners you contacted understand the Electrical aspects prior to the generated power
getting to the panel, and have made those corrections, its more than likely that none of these suggestions would make it Code Compliant.
Click to expand...

So how would suggest this be setup to make it code compliant?
 
infinity said:
So how would suggest this be setup to make it code compliant?
Click to expand...

I wouldnt make any suggestions to a portable generator owner as to how it should be set up if he or she is trying to do it themselves for the simple fact that they would'nt understand anyway.

A generator ( Portable or Not) should be put into service by someone who knows all the requirements that need to be met.


There's way too many requirements that have to be met prior to connecting a generator to an electrical system.

And your going to try and explain all of this over the phone to somebody who just ran down to Home Depot and picked up a generator so he could somehow get his lights back on? I doubt it.
 
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