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Generator to back feed house from garage

pstemari

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Seattle
I can guarantee you that if you feed 240VAC into the secondary of your pole pig, the primary will be at full line voltage. That's how transformers work. You won't be able to drive it with full current, but it only takes a few milliamps to kill someone.

You could potentially use a lockout with two padlocks and two keys, where normally the generator key is locked to the main panel. To activate the system you first kill the main breaker, unlock the first padlock, remove the garage key, and then lock the main disconnect off. You then go to the garage, unlock the generator breaker, flip it on, and then lock the main key to the garage panel.

That's not a perfect solution, since nothing stops you from unlocking one panel, taking the key, and unless the other, but it's semi-plausible.

Regardless, if an inspector or power company employee saw such a setup, I would expect that they would pull your meter and lock out your electricity until you removed it and replaced it with a proper transfer switch.

The only way I think they might approve it is if you had a system where the keys were captive and you couldn't physically remove the garage key until the breaker was locked in the off position. You can't do that with padlocks and simple lockout brackets.

Sent from my Pixel XL using Tapatalk
 
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mm08822

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Yes it would!!!!!

IMHO
The chances of a 1 kilowatt generator feeding back threw the community & doing any damage to anyone or anything are so incredibly slim its hardly even worth talking about.

Linemen treat all wires as live = no problem

Your small generator WILL trip its breaker almost instantly if you did back feed. It can not possibly power up all the draw that's there & will kick off almost right away = no problem.

I don't know 100% for sure but I was told (by hydro one) that a typical home generator does not have enough power to power up a transformer. making the fabled mega voltage non existent =no problem

IF one is not a complete idiot or without any common sense then OK. Realistically tho, it's so incredibly simple to follow a basic set predetermined actions that will make it totally safe. In reality its 100 times easier than driving. And many people get threw a lifetime of driving without incident.

OP, the fear mongers are alive & well. You do what you feel is right.
Personally I will not be coerced threw unreasonable fear to hand over a couple years worth of electricity payments for no logical reason. The fear is there to scare you into giving the people who are trying to scare you a pile o cash. Be taken if you want.

Steve

__________________
Disclaimer: What I say is based on my knowledge and experience only. It's entirely possible I'm full of ****. You've been warned!! "tdkkart"

"Make the most you can of the Indian Hemp seed and sow it everywhere." George Washington

I was very relieved once I finally made it through to your disclaimer.
 

Alchymist

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Central PA
Yes it would!!!!!


OP, the fear mongers are alive & well. You do what you feel is right.
Personally I will not be coerced threw unreasonable fear to hand over a couple years worth of electricity payments for no logical reason. The fear is there to scare you into giving the people who are trying to scare you a pile o cash. Be taken if you want.

Disclaimer: What I say is based on my knowledge and experience only. It's entirely possible I'm full of ****. You've been warned!! "tdkkart"

Steve

I was very relieved once I finally made it through to your disclaimer.

:lol_hitti:lol_hitti

Not only possible, but quire probable. :bounce:
 

mm08822

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Even NFPA 70 will stumble if asked what constitutes a "Qualified Person" -- simply and eventually declaring "someone who knows what they are doing" - similar to OSHA definition.

We are all entitled to our own interpretations, and I am comfortable reading that simply opening the main disconnect satisfies the article.

You are not reading your own cite, in particular the part that provides isolation via lockable means. In this case, a simple disconnect with a padlock feature satisfies the requirement. ....... In that regard, someone opening the main CB and installing a LOTO device, a lockable means would be just peachy.

Let me help you interpret.

2017 NEC 702.5 Exception: Temporary connection of a portable generator without transfer
equipment shall be permitted where conditions of maintenance and supervision ensure that only qualified persons will service the installation, and where the normal supply is physically isolated by a lockable disconnecting means or by the disconnection of the normal supply conductors.

2017 NFPA 70 definition…… Qualified person. One who has skills and knowledge related to the construction and operation of the electrical equipment and installations and has received safety training to recognize and avoid the hazards involved.

Now read the exception again……split out into two simpler sentences.

Exception: Temporary connection of a portable generator without transfer
equipment shall be permitted where conditions of maintenance and supervision ensure that only qualified persons will service the installation, and where the normal
supply is physically isolated by a lockable disconnecting means.

Exception: Temporary connection of a portable generator without transfer
equipment shall be permitted where conditions of maintenance and supervision ensure that only qualified persons will service the installation, and by the disconnection of the normal supply conductors.

Read one more time……….with the qualified person definition inserted.

Exception: Temporary connection of a portable generator without transfer
equipment shall be permitted where conditions of maintenance and supervision ensure that ONLY one who has skills and knowledge related to the construction and operation of the electrical equipment and installations and has received safety training to recognize and avoid the hazards involved will service the installation and where the normal
supply is physically isolated by a lockable disconnecting means.

Exception: Temporary connection of a portable generator without transfer
equipment shall be permitted where conditions of maintenance and supervision ensure that ONLY one who has skills and knowledge related to the construction and operation of the electrical equipment and installations and has received safety training to recognize and avoid the hazards involved will service the installation and by the disconnection of the normal supply conductors.

If this hasn’t helped you then it is obvious you want to do it your way regardless of what you are told and have no real-world experience that s**t happens.

Also read the Alchymist’s reply again.
 

mm08822

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The only way I think they might approve it is if you had a system where the keys were captive and you couldn't physically remove the garage key until the breaker was locked in the off position. You can't do that with padlocks and simple lockout brackets.

This is a great solution! I remember these on switchgear tie-breakers from years back. These are typically found in industrial environments, but for the OP’s situation/want, it makes for the equivalent of an interlock. Kirk key interlocks is what we used. Now there are many mfrs’ offering similar. I’m certain the price is too $$$ for the residential market, but need to call around.

However, to further detail your suggestion, it would be implemented as follows:

The Main Panel would have trapped key interlock on the main cb. Key would be captive while the cb was in the closed position. The key could only be removed when cb is in the off position.
The sub-panel would have a 50A (30A?) 120/240vac branch-circuit connected to it with a flanged plug at the end. (typical power inlet box) The same key would be then used to close the branch circuit breaker at the sub-panel. This would prevent the plug stabs from being hot and could only back-feed the main panel when main cb open. Now an extension cord (cap and plug) could be used to connect the generator to the sub-panel.

This solution eliminates:
suicide cords,
improper main breaker position,
risk of back-feed to the grid,
blowing up the generator,
arc flash exposure to the person closing a breaker at the wrong time.

http://keyinterlocking.com/Images/Index/Pdf/VF Tech Sheet.pdf
 

Falcon67

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Merkel, TX
I would bet that in court, a "qualified person" would be put forth as an individual trained and licensed. "Homeowner' would not fit that description, without regard to any stated experience. Maybe if holding a local certificate that allows a homeowner to pull their own permit - a requirement here. At least in Texas you can't buy a pickup and write "ELECTRICIAN" on the side and start taking work - well, not legally. Same with fire protection. Our on site licensed sparkys here at work can't mess with the fire alarm systems other than check the batteries.
 

Alchymist

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Half the posts in this thread are just attempts at justification for doing things their way, regardless of the advice of knowledgeable people.
 

BlackJackJim

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Messages
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Half the posts in this thread are just attempts at justification for doing things their way, regardless of the advice of knowledgeable people.

Yes - self-certifying knowledgeable people..and there are many. Pulling a code cite in itself and then wrapping it with your own salad dressing, and absent any precedence or past rulings from either AHJs or even the code-making bodies is a simple opinion with no more weight than if written by a baboon. This is one of the problems with the Internet and such fora. You are likely to get as many interpretations as there are people, and who knows really what the true answer is. Kinda like a black hole - you toss in a book and out comes a chair.

I will reiterate: I use a RV type weather receptacle as shown in the photos wired to a 50A breaker. When I need to engage the gas generator, I shut off the main disconnects and power up the generator and close the respective breakers. The AHJ knows what I am doing and has no heartburn and indicates that he does the same. If that troubles you then go sit in the dark and selectively markup your code cites by candle light.

image1.jpg

image2.jpg
 

Alchymist

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Yes - self-certifying knowledgeable people..and there are many. Pulling a code cite in itself and then wrapping it with your own salad dressing, and absent any precedence or past rulings from either AHJs or even the code-making bodies is a simple opinion with no more weight than if written by a baboon. This is one of the problems with the Internet and such fora. You are likely to get as many interpretations as there are people, and who knows really what the true answer is. Kinda like a black hole - you toss in a book and out comes a chair.

I will reiterate: I use a RV type weather receptacle as shown in the photos wired to a 50A breaker. When I need to engage the gas generator, I shut off the main disconnects and power up the generator and close the respective breakers. The AHJ knows what I am doing and has no heartburn and indicates that he does the same. If that troubles you then go sit in the dark and selectively markup your code cites by candle light.

So do you consider your posts the writings of a baboon? (Just wondering).

There are people on here that are actual electricians, such as norcal, theoldwizard1, wyliesdiesels, and others who have many many posts on electrical subjects, and if you were a longtime member, you would have recognized they put out the facts, and vary rarely do they miscue on anything.

As to what you do for your setup, your concern, just don't advocate others doing it.
 
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yeldogt

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Yes - self-certifying knowledgeable people..and there are many. Pulling a code cite in itself and then wrapping it with your own salad dressing, and absent any precedence or past rulings from either AHJs or even the code-making bodies is a simple opinion with no more weight than if written by a baboon. This is one of the problems with the Internet and such fora. You are likely to get as many interpretations as there are people, and who knows really what the true answer is. Kinda like a black hole - you toss in a book and out comes a chair.

I will reiterate: I use a RV type weather receptacle as shown in the photos wired to a 50A breaker. When I need to engage the gas generator, I shut off the main disconnects and power up the generator and close the respective breakers. The AHJ knows what I am doing and has no heartburn and indicates that he does the same. If that troubles you then go sit in the dark and selectively markup your code cites by candle light.

image1.jpg

image2.jpg

Guess I don't understand why you would go that far and not do it correctly for another $100 bucks ... Adding a dedicated sub like the Square D designed for essentials w/ built in lockout.

You can't have the connection point for a generator active with the main active -- it has to be a switch that prevents this and can't be predicated on someone knowing to do it .. having the panel with a lock does not fix this problem. Also, there is no main as the back feeded breaker is not functioning or approved.

People will do what they will, but I think it's important to explain the various ways to do it correctly ... in many cases it's not much more difficult.
 
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udderlyoffroad

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Bristol, UK
This has been an illuminating thread, and to me the manual option+ hot male plug just seems way too error prone, especially if you’ll likely be under pressure when doing this. Also, in the unlikely event something goes wrong, and they catch you, I can see the book being thrown at you by the state prosecutor?

This video might be interesting, he takes apart a Chinese auto-transfer switch made for the European market, designed to be installed upstream of the main panel. Would a UL-rated version of that meet NEC?

Another thing, you guys are all taking about running generators <inside> your garages? How are you dealing with the exhaust? Seems like another Darwinian moment just waiting to happen right there.
 

yeldogt

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This has been an illuminating thread, and to me the manual option+ hot male plug just seems way too error prone, especially if you’ll likely be under pressure when doing this. Also, in the unlikely event something goes wrong, and they catch you, I can see the book being thrown at you by the state prosecutor?

This video might be interesting, he takes apart a Chinese auto-transfer switch made for the European market, designed to be installed upstream of the main panel. Would a UL-rated version of that meet NEC?

Another thing, you guys are all taking about running generators <inside> your garages? How are you dealing with the exhaust? Seems like another Darwinian moment just waiting to happen right there.


That guy really gets into it ! My auto transfer switch uses the same principle excepts it's using relays vs a switch.
 

BlackJackJim

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Messages
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So do you consider your posts the writings of a baboon? (Just wondering).

There are people on here that are actual electricians, such as norcal, theoldwizard1, wyliesdiesels, and others who have many many posts on electrical subjects, and if you were a longtime member, you would have recognized they put out the facts, and vary rarely do they miscue on anything.

As to what you do for your setup, your concern, just don't advocate others doing it.

Same goes for you buddy -- here .....have a banana.
 

wyliesdiesels

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Location
Modesto, CA
wow

just wow.

No words.

The jackasses certainly came out in this thread.

I really dont get the bad attitude some on here have insisting on doing things the cheapskate lazy way that will only end someone's life.

Someone is just asking for a manslaughter charge on their record.... smh *faceplam
 

mm08822

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Messages
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NJ
Yes - self-certifying knowledgeable people..and there are many. Pulling a code cite in itself and then wrapping it with your own salad dressing, and absent any precedence or past rulings from either AHJs or even the code-making bodies is a simple opinion with no more weight than if written by a baboon. This is one of the problems with the Internet and such fora. You are likely to get as many interpretations as there are people, and who knows really what the true answer is. Kinda like a black hole - you toss in a book and out comes a chair.

I will reiterate: I use a RV type weather receptacle as shown in the photos wired to a 50A breaker. When I need to engage the gas generator, I shut off the main disconnects and power up the generator and close the respective breakers. The AHJ knows what I am doing and has no heartburn and indicates that he does the same. If that troubles you then go sit in the dark and selectively markup your code cites by candle light.

image1.jpg

image2.jpg


First off...it is a flanged plug, not a receptacle.

If the cb for that plug circuit is not interlocked with the power source cb in that panel and your AHJ approved that, then he is useless and should have his license pulled.
Also, a 30A plug on a 50A cb?
What size wire did you use? 14?

Glad you are self-certified. I see it's working for you.
Hey Jim....you smell something burning??
 
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