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hardwire portable generator to load center via interlock kit and breaker

hardwire portable generator to load center via interlock kit and breaker

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  #1  
Old 11-07-11, 03:23 PM
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hardwire portable generator to load center via interlock kit and breaker

Hello,
Pardon the newbie question. I have purchased a 30 amp 7500w portable generator that I was going to connect to the house via a reliance controls 10 circuit 30amp transfer switch kit. However after doing some poking around I found that you can use a back feed double pole 30 amp breaker with an interlock kit (manufactured by Square D as I have a Square D homeline load center). My question / problem I am hoping you can help with is as follows: (see pics)

I would like to remove and unused 50 amp double breaker on the RH lower side of my load center and relocate the single breakers on the RH down 2 spaces to make room for the 30 amp double breaker that the generator would feed into. I need the breaker to be in the 2/4 position so that it can interact with the required interlock plate and the 200amp main breaker so I cannot back feed to the utility when the gen is in use. Am I able to move these breakers down or is that going to position them so that the box is no longer balanced (if that makes sense). I thought every other spot was connected to the opposite side.. Thank you in advance for any information on this.

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  #2  
Old 11-07-11, 03:29 PM
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The top two breakers can be relocated to the bottom positions to make room for the generator interlock kit. You may use wirenuts and short lengths of wire to extend the circuits if necessary to reach the new breaker positions.
 
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Old 11-07-11, 03:46 PM
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Thanks for your reply. I was not sure if I was allowed to use wire nuts and extend that wire for those breakers or not. That is why I was going to shift the whole row of breakers down after removing the unused double breaker for the stove. However from what you are saying that is not a good idea / possible?
 
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Old 11-08-11, 07:34 AM
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One more ?

From what I can find it is ok to use appropriate size wire nuts and matching gauge wire to extend the hot leg for the two breakers I wish to relocate further down the box. Is there any real safety issue with running a 7500W portable generator into the load center this way? I have come across something about the bonded neutral on the generator etc.. I have seen quite a few videos of people seemingly running portables this was using the interlock kit without issue. Thanks again for responses.
 
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Old 11-08-11, 07:44 AM
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Here is some great info on the whole gen bonding, grounding, ground fault thing.

http://www.oshaprofessor.com/Portabl...rds%203-05.pdf

Mike NJ
 
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Old 11-08-11, 10:23 AM
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Originally Posted by madmatt76 View Post
However from what you are saying that is not a good idea / possible?
It's possible, just more work to move and re-label 20 breakers rather than 2.

Is there any real safety issue with running a 7500W portable generator into the load center this way? I have come across something about the bonded neutral on the generator etc..
No there is not a safety issue as long as you use an approved interlock and appropriate inlet and generator cord. The best thing to do with your generator if it will only be used to power the house is to modify it and remove the ground-neutral bond. If however the generator will be used for jobsite power, the ground-neutral bond must remain intact. That is a safety issue.

Honestly I'm not really sure there is any safety issue at all with leaving it intact for powering the house, so my preference would be to leave it intact. This statement is on the grounds that 1) it is a non-issue when powering the house; and 2) it is necessary for safety to keep the ground-neutral bond intact on a stand-alone generator. You can't really say for certain the generator will never be used standalone, so it's better to leave the bond in place so it is safe to use standalone if that situation ever comes up (long after you have forgotten about the bonding issue).
 
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Old 11-08-11, 10:32 AM
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1) it is a non-issue when powering the house; and 2) it is necessary for safety to keep the ground-neutral bond intact on a stand-alone generator. You can't really say for certain the generator will never be used standalone, so it's better to leave the bond in place so it is safe to use standalone if that situation ever comes up (long after you have forgotten about the bonding issue).
Isnt it common knowledge to not have two bonded areas such as at the gen and the panal? Isnt that just asking to get killed?

I am not an electrician but based on what I read, from that OSHA link I posted.

Mike NJ
 
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Old 11-09-11, 06:46 AM
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Thanks again for your replies. I have the approved external outlet for plugging the generator, appropriate wire size for wiring it to the double pole breaker, neutral bar and ground bar in the load center. Of course this will have to wait as my generator is on back order for 8 weeks. Thanks again guys !
 
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Old 11-09-11, 08:08 AM
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have the approved external outlet
That was a typo wasn't it? You need an inlet (male) not an outlet (female).
 
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Old 11-09-11, 10:20 AM
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Originally Posted by lawrosa View Post
Isnt it common knowledge to not have two bonded areas such as at the gen and the panal? Isnt that just asking to get killed?
It's generally better not to, but there are very limited circumstances where it is truly dangerous.
 
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Old 11-09-11, 02:02 PM
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Yeah, I got the male 240 generator inlet plug for the outside of the house.
 
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Old 11-28-11, 12:01 PM
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Ok, one more time. My gen is finally arriving tomorrow. I am still confused on the whole neutral bonding issue with the gen being hooked up to the house via an inlet box, and a back feed breaker with interlock kit (I wasn't going to do the transfer switch). I read the PDF that was put up. As a stand alone say job site application I see it has to stay attached. However is using it to power the home connected to the panel a danger to leave the gen neutral bonded to frame in tact ? I have seen some videos of others doing this with no mention of disconnecting the gen neutral to frame (and they were not using a transfer switch)....doesn't mean it's correct by all the code I guess. Thanks for any repeated or additional advice.
 
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Old 11-29-11, 08:47 AM
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Shameless bump.......................................
 
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Old 11-29-11, 09:12 AM
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Your supposed to have only one bonding point from what I understand the code to be. Either bond at the gen or the panal but not both. And with an interlock you cant really unbond at the panal. Make sense?

Mike NJ
 
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Old 11-29-11, 12:32 PM
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Originally Posted by lawrosa View Post
Your supposed to have only one bonding point from what I understand the code to be. Either bond at the gen or the panal but not both. And with an interlock you cant really unbond at the panal. Make sense?

Mike NJ
So since my cord from the gen to the inlet box to the load center will be grounded and connected to the load center neutral I should disconnect the neutral bonded to frame on the gen? Is this mostly just a code thing?
 
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Old 11-29-11, 01:08 PM
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Thats my take on the code.

And if you every use the generators other outlets plug the gen into the home inlet so its bonded.

If you use the gen say in the yard where its stand alone take a plug and wire the gound and neutral to bond the gen. Then plug it into the gen.

Like this.




To be sure all is correct use a device like this to check all the outlets.



When you check the gen outlets when the gen is plugged into the home all outlets should show normal.

If you plug in the device to the gen when its not plugged into the home it will show as an open ground.

Thats how my gen is. If I use my gen in the yard I just plug into the house to get the bond. If I take the gen to a job site or use for the RV I plug my adapter into one of the duplex outlets to bond it.

Mike NJ
 
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Old 11-29-11, 04:24 PM
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Originally Posted by lawrosa View Post
Thats my take on the code.

And if you every use the generators other outlets plug the gen into the home inlet so its bonded.

If you use the gen say in the yard where its stand alone take a plug and wire the gound and neutral to bond the gen. Then plug it into the gen.

Like this.




To be sure all is correct use a device like this to check all the outlets.



When you check the gen outlets when the gen is plugged into the home all outlets should show normal.

If you plug in the device to the gen when its not plugged into the home it will show as an open ground.

Thats how my gen is. If I use my gen in the yard I just plug into the house to get the bond. If I take the gen to a job site or use for the RV I plug my adapter into one of the duplex outlets to bond it.

Mike NJ

Thanks a lot Mike. I will get one of those, they look handy. Now it's down to installation and waiting for the tri-fuel adapter to arrive.
 
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Old 12-22-11, 10:09 PM
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Thanks for all your info. I finally have it all set up. I have to a test run tomorrow. I did my natural gas piping to get my gen to run on natural gas / propane or gasoline. Took the neutral to ground bond off at the gen, made a shorting plug for stand alone operations and placarded the generator for floating neutral. I did find a loose breaker when shutting down the panel for work. I was a bit annoyed that the contractor that did the install when building the house (2006) left me with a cracked loose arcing breaker.
Anyway, wish me luck on the test run tomorrow. Either going to be success or smoke
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Old 12-24-11, 08:31 AM
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deleted mmmmmmmmmmmmmmmmmmmmmmm.
 
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Old 12-24-11, 12:23 PM
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Your install looks very professional.
 
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Old 12-24-11, 09:36 PM
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Originally Posted by AllanJ View Post
deleted mmmmmmmmmmmmmmmmmmmmmmm.

What was deleted ? If so what ?
 
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Old 12-26-11, 07:12 AM
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Granted, neutral and ground may be bonded in only one place but ...
I would not re-arrange my main panel, separating neutrals and grounds, for the sole purpose of connecting in a portable generator for once in awhile use.
I would not pry apart a generator to get at a hard to reach neutral and ground bonding.
Originally Posted by madmatt76 View Post
What was deleted ? If so what ?
This forum requires a minimum 25 characters for a reply and "deleted" is less than 25 chars.
 
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Old 12-26-11, 02:57 PM
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Thanks. I did not realize I made a post of less than 25. Been a long week or two...

I did not rearrange the neutral bond at the panel. Just moved some breakers to add another and remove an unused one. The gen part wasn't bad at all. Four screws and a small jumper wire.
 
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Old 07-09-12, 10:01 PM
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Removing bonding wire

I don't think is good idea to remove the bonding wire an less you have to.
I see all the time people feeding their house and sharing and extension cord to the neighbors, that cord will be missing the ground if you've removed the bonding wire.
 
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Old 07-09-12, 10:23 PM
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Sergio,

Welcome to the forums, and thank you for your input, but this thread is more than six months old.
 
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Old 07-09-12, 10:27 PM
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"Sergio2


'I don't think is good idea to remove the bonding wire an less you have to.
I see all the time people feeding their house and sharing and extension cord to the neighbors, that cord will be missing the ground if you've removed the bonding wire.'"


Im not sure why you felt the need to resurrect a six month old thread :NO NO NO: , but you are incorrect sir. The cord to the neightbor would still be grounded AND bonded to the neutral at the panel via the power inlet cord.
 
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Old 07-10-12, 07:06 AM
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On some generators it is intended that the neutral-ground bond inside be removable and replaceable and then the bond should be removed when hooking up to home electrical systems. Just don't lose the bonding jumper in case you need it for use of the generator away from home.

When you plug an extension cord into a generator and at the far end the neutral and equipment grounding conductor (ground wire) are bonded or faulted, any hazard would occur at the far end, not at the generator. Because the generator is the final return point for the current it generates, having its body bonded or faulted to neutrals does not create a hazard there.

Meanwhile, if at the far end of the extension cord, the EGC is grounded, such as being at the neighbor's properly wired panel with grounding electrode conductor, any hazard of neutrals bonded or faulted to ground there is eliminated.

I would not hard wire a generator (no male receptacle on the side of the house together with patch cord to generator) while leaving neutral and ground bonded both at the generator and at the panel.
 

Last edited by AllanJ; 07-10-12 at 07:52 AM.
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