Another Generator Grounding Question

[goldstar]

I understand what you are saying but it is all rhetorical. IF is probably the largest word in our language. What IF this, what IF that. IF I turned down the job because I could not follow the code then I could live with my conscience. I am looking at the situation this way. On one hand you have a home owner who may have very little or no electrical experience. If I connect it the way that it is described above and IF there is some failure in the wiring and it energizes the non-cc parts and/or the frame of the generator and the HO goes to service the generator and is killed then I would be clearly at fault. On the other hand IF a HO makes up a suicide cord and plugs it in and back feeds on the utility the POCO workers are supposed to be trained and equipped to handle these types of situations. I am not saying it has never happened or that it will never happen again but with the abundance of HO's with generators now verse the past I am sure the POCO's have addressed the situation and how to deal with it.

You are correct. IF is, in many cases, one of the largest words in the English language. Please bear with me on this - IF jwelectric had never brought the UL White Book to the attention of this Forum, would you or anyone else here have known about UL-FTCN ? (BTW, I'm not bashing jwelectric for bringing this up AGAIN. We've been friendly adversaries for years here in the Forum). But, it's apparent that generator manufacturers are not aware of this section because they are pushing product out the door in record #'s. I carry the NEC book in my work van with me at all times. But, I do not carry the UL White book or any other Code reference book. If I did I'd need a library section set off to the side of the truck.

 

[ceb58]

Not saying it is allowed. Just saying it is not the worst thing.

That is because when it is a sub-panel there is some metal parts involved that will end up with some neutral current on them. For a portable generator the connection is a rubber cord 99.9% of the time.

Please explain how it is different. Metal main panel, feeders to sub-panel which are covered in insulation, metal sub- panel. Neutral goes bad current on metal.
Generator metal frame, engine and armature, feeders to panel that are covered in insulation, metal panel.
The fact that there is an SJ or SO cord between the generator and panel doesn't prevent unwanted current on the non-current carrying parts no more that SER would prevent it in a panel - sub-panel situation.

 

[ceb58]

You are correct. IF is, in many cases, one of the largest words in the English language. Please bear with me on this - IF jwelectric had never brought the UL White Book to the attention of this Forum, would you or anyone else here have known about UL-FTCN ? (BTW, I'm not bashing jwelectric for bringing this up AGAIN. We've been friendly adversaries for years here in the Forum). But, it's apparent that generator manufacturers are not aware of this section because they are pushing product out the door in record #'s. I carry the NEC book in my work van with me at all times. But, I do not carry the UL White book or any other Code reference book. If I did I'd need a library section set off to the side of the truck.

I agree that if Mike had not brought it up then we would still been wandering in the wilderness.
I also agree that it is very hard to keep up with every thing and still make a living unless making a living is keeping up with this stuff. I do disagree with your statement about the manufactures. It is not them that is hooking the portable generator up in a manner that they did not intend it to be hooked up. They manufacture these units for people to plug in a drop cord to temporarily operate equipment and/or lights. It is others that have come up with ways to connect these units to the buildings wiring system IE: interlocks, man. trans. switch and so on. Which now brings us back full circle to the statement put out by UL.
We can debate this issue until we run out of ink on these computers. I know what I will/have done in these situations. I cannot speak for you or anyone else as to what you would or would not do. All I am saying is it is in black and white, no gray area, as to what should be done.

 

[ActionDave]

Please explain how it is different.....

It's no different than feeding a separate building with no other metal connections with three wirres and re-bonding the neutral. That was a legit install until '05 code.

 

[GoldDigger]

It's no different than feeding a separate building with no other metal connections with three wires and re-bonding the neutral. That was a legit install until '05 code.

Regardless of code, it becomes a practical problem if there are main or feeder level GFCI breakers involved in the system. And generators that include a GFCI may not make it easy for you to bypass it when when hard wiring them as backups.
That is the largest practical reason to provide a switched neutral, IMHO.

 

[ActionDave]

Regardless of code, it becomes a practical problem if there are main or feeder level GFCI breakers involved in the system. And generators that include a GFCI may not make it easy for you to bypass it when when hard wiring them as backups.
That is the largest practical reason to provide a switched neutral, IMHO.

This is true. When GFI is involved you need a switched neutral or your honkered for sure.

I was generalizing a bit more, while you have specialized down to the nub of it.

 

[goldstar]

I agree that if Mike had not brought it up then we would still been wandering in the wilderness.
I also agree that it is very hard to keep up with every thing and still make a living unless making a living is keeping up with this stuff. I do disagree with your statement about the manufactures. It is not them that is hooking the portable generator up in a manner that they did not intend it to be hooked up. They manufacture these units for people to plug in a drop cord to temporarily operate equipment and/or lights. It is others that have come up with ways to connect these units to the buildings wiring system IE: interlocks, man. trans. switch and so on.

This is mainly where we disagree. If you take a simple 7.5KW portable generator made by Generac, they will have (2) 20 amp duplex receptacles and one of these cute little 30 amp receptacles built into the unit

http://www.electricgeneratorsdirect.com/images/plug_image14.jpg .

They will also have packages like these which do not transfer the neutral BTW :

http://www.electricgeneratorsdirect.com/Generac-EGD-5943KIT-Portable-Generator/p8962.html

As long as these portables come equipped with a 30 or 50 amp 120/240V receptacle, HO's will be using them to connect power to their house wiring in some manner. As long as EI's in my area are accepting these installations I will be performing the installations knowing that I'm, at the very least, doing it much more safely than a HO would.

In addition, with companies like EG Direct (as well as HD & Lowe's) pushing product out their doors it's difficult to tell a HO who, by the way, did not want to have to purchase a $1K generator in the first place, that he now has to have a 3-pole manual transfer switch installed that probably costs another $300 + installation.

Which now brings us back full circle to the statement put out by UL.
We can debate this issue until we run out of ink on these computers. I know what I will/have done in these situations. I cannot speak for you or anyone else as to what you would or would not do. All I am saying is it is in black and white, no gray area, as to what should be done.

I'm not trying to convince you that my way is the correct way. You and I and everyone else involved in this thread now know what's written in UL-FTCN. What I'm trying to point out is that numerous companies have launched massive sales campaigns for portable generators that are designed to appeal to the common HO, the vast majority of whom would not know how to connect these generators to their house wiring. These campaigns are like a snowball rolling downhill. In any event, I will continue to perform these installations in my area as long as they accepted by the EI's. When that stops or when jwelectric launches his campaign to convince the EI's in the 50 States that we should be following UL-FTCN then I'll stop.

 

[jwelectric]

I don?t know the laws in NJ but I do know the laws in NC. Here it is illegal to install anything that is not tested by a NRTL to a dwelling unit.

If the generator has receptacles mounted on the frame and the neutral is bonded to the frame it will most likely be listed.

110.3(B) requires that any listed piece of equipment be installed according to any instructions included in the listing of said equipment and UL FTCN is those instructions.

Here in NC the contractor is responsible for making a compliant installation even if the code official says it is alright. Should an electrical contractor install one of these generators using a method that is non-compliant and an inspector passes it and the home owner get hurt the electrical contractor is liable and can lose their license.

As a sworn inspector should I see one installed in a non-compliant manner in my jurisdiction I will post a condemnation on that property until the installation conforms to the laws adopted in my jurisdiction.
As a contractor I could care less how the home owner installs anything as I am not going to be held liable.

 

[goldstar]

Mike, I have always had a tremendous amount of respect for you and as I've already mentioned we've been friendly adversaries in this Code Forum for a long time. I understand your position on this and, as you pointed out, the position NC has taken. If and when NJ adopts that position, then and only then, will I stop making these types of installations. Until then I will continue to make $$ and my conscience will be clear knowing that I made a 100% more safe installation than a HO would have.

With respect to the subject of liability, we are all subject to the liabilities that any electrical job comes with. Making safe connections of a portable generator bears no more responsibility than making safe connections of a permanently installed NG or LP unit.

This is an excerpt from the owners manual of a Generac 7.5KW portable generator. Nowhere in the manual does it make reference to UL-FTCN. I would think that if Generac intended to cite that section it would be here in this section.

STANDARDS INDEX

1. National Fire Protection Association (NFPA) 70: The NATIONAL ELECTRIC CODE (NEC) available from www.nfpa.org

2. National Fire Protection Association (NFPA) 5000: BUILDING CONSTRUCTION AND SAFETY CODE available from www.nfpa.org

3. International Building Code available from www.iccsafe.org

4. Agricultural Wiring Handbook available from www.rerc.org , Rural Electricity Resource Council P.O. Box 309 Wilmington, OH 45177-0309

5. ASAE EP-364.2 Installation and Maintenance of Farm Standby Electric Power available from www.asabe.org, American Society of Agricultural & Biological Engineers 2950 Niles Road, St. Joseph, MI 49085

This list is not all inclusive. Check with the Authority Having Local Jurisdiction (AHJ) for any local codes or standards which may be
applicable to your jurisdiction.

I'm not disputing what is written in UL-FTCN. What I am saying is that if these generator companies started citing that section they would no longer be able to manufacture units with 120/240V receptacles, they would not market 4-prong power cords or 4-prong power inlet ports and would no longer make transfer panels that are used with portable units.

 

[qcroanoke]

Until then I will continue to make $$ and my conscience will be clear knowing that I made a 100% more safe installation than a HO would have.

I agree.
I've done a few installs with the interlock kits but the neutral was not bonded in the generator and because of that the unit was not UL listed. So which is worse?
I have done this because as Goldstar said it was a far safer install than they would have done......

 

[templdl]

I agree.
I've done a few installs with the interlock kits but the neutral was not bonded in the generator and because of that the unit was not UL listed. So which is worse?
I have done this because as Goldstar said it was a far safer install than they would have done......

Back to my previous post. It's if the neutral is bonded with the EGC at the genset is the starting point. In the neutral is insulated and isolated from the EGC. If not a switching neutral is required with a transfer scheme in order to avoid the neutral being attached to the EGC at more than the SE. What you don't want is the neutral to be bonded to the EGC at both the SE and at the Genset.

 

[qcroanoke]

Back to my previous post. It's if the neutral is bonded with the EGC at the genset is the starting point. In the neutral is insulated and isolated from the EGC. If not a switching neutral is required with a transfer scheme in order to avoid the neutral being attached to the EGC at more than the SE. What you don't want is the neutral to be bonded to the EGC at both the SE and at the Genset.

That's not what I asked. Sorry.
I asked which is worse. A UL listed genset with a bonded neutral hooked up to a house like we have been discussing that is wrong or a non-UL listed genset without a bonded neutral hooked up as we have been discussing?
Either way it's wrong.

 

[templdl]

That's not what I asked. Sorry.
I asked which is worse. A UL listed genset with a bonded neutral hooked up to a house like we have been discussing that is wrong or a non-UL listed genset without a bonded neutral hooked up as we have been discussing?
Either way it's wrong.

Switched neutral if that's your point then.

 

[jwelectric]

That's not what I asked. Sorry.
I asked which is worse. A UL listed genset with a bonded neutral hooked up to a house like we have been discussing that is wrong or a non-UL listed genset without a bonded neutral hooked up as we have been discussing?
Either way it's wrong.

I will let you answer that question yourself.

In a non-bonded genset that is being used as a temp power source for 120 volts and something happens to a winding then instead of 120 volts one could possibly have 240 volts supplying that 120 volt appliance. Examples; using the genset to operate a hedge clipper, or to use a battery charger for dead battery, a hand tool such as a drill or saw, just to mention a few.

A bonded genset used to power a home during inclement weather where the EGC is carrying current back to the frame of the gneset and the homeowner is touching this frame standing on possibly wet ground within feet of the grounding electrode of the service equipment. Now there is the third parallel path for that current to flow.

Both have been documented so which is worse?

 

[templdl]

I will let you answer that question yourself.

In a non-bonded genset that is being used as a temp power source for 120 volts and something happens to a winding then instead of 120 volts one could possibly have 240 volts supplying that 120 volt appliance. Examples; using the genset to operate a hedge clipper, or to use a battery charger for dead battery, a hand tool such as a drill or saw, just to mention a few.

A bonded genset used to power a home during inclement weather where the EGC is carrying current back to the frame of the gneset and the homeowner is touching this frame standing on possibly wet ground within feet of the grounding electrode of the service equipment. Now there is the third parallel path for that current to flow.

Both have been documented so which is worse?

As you so aptly pointed out the most important thing to be learned here is an understanding and appreciation of the danger of the application. Hopefully it removes ignorance of a potentially dangerous installation and as such it now provides a choice.
All to often there are all to many that don't have a clue about what the implications are when the neural and EGC are bonded at the genset.

 

[goldstar]

In a non-bonded genset that is being used as a temp power source for 120 volts and something happens to a winding then instead of 120 volts one could possibly have 240 volts supplying that 120 volt appliance. Examples; using the genset to operate a hedge clipper, or to use a battery charger for dead battery, a hand tool such as a drill or saw, just to mention a few.

That could just as easily happen to a workman on a jobsite using a portable when no utility power is available.

A bonded genset used to power a home during inclement weather where the EGC is carrying current back to the frame of the gneset and the homeowner is touching this frame standing on possibly wet ground within feet of the grounding electrode of the service equipment. Now there is the third parallel path for that current to flow.

As long as we're making assumptions in these scenarios why don't we also say that the HO went out to check on the generator, was barefoot while stepping in a puddle and rested his hand on top of the electric meter while he was taking the gas cap off the generator to see if it needed gas while he was smoking a cigar ?

Both have been documented so which is worse?

What's worse is making up "IF" scenarios for every possibility imaginable to support your point of view. What IF the crimp on the neutral up on the pole just happened to corrode during a storm causing somewhere short of 240 volts to be delivered to every 120 V circuit in a house causing everything electronic to now be toasted ? It's a shot in a million but that's been documented too BTW.

BTW, I love your stories Mike.

 

[jwelectric]

That could just as easily happen to a workman on a jobsite using a portable when no utility power is available.
As long as we're making assumptions in these scenarios why don't we also say that the HO went out to check on the generator, was barefoot while stepping in a puddle and rested his hand on top of the electric meter while he was taking the gas cap off the generator to see if it needed gas while he was smoking a cigar ?

What's worse is making up "IF" scenarios for every possibility imaginable to support your point of view. What IF the crimp on the neutral up on the pole just happened to corrode during a storm causing somewhere short of 240 volts to be delivered to every 120 V circuit in a house causing everything electronic to now be toasted ? It's a shot in a million but that's been documented too BTW.

BTW, I love your stories Mike.

Take a few minutes and do the research on the accidents documented with the use of portable generators. These are not stories but documented facts.

If the workman on the jobsite is using a portable generator that is bonded then he would never know that the winding failed.

No assumption was made but even barefooted standing in water the touching of a properly installed meter base has no danger, but if they are wearing wet shoes and an improperly installed generator touching the meter could lead to death, documented.

No the worse case is someone who thinks that the word "safer" in some way relieves safety. Playing Russian Rolette with one bullet is safer than a fully loaded gun wouldn't you say. So let's play but you go first.

 

[texie]

Take a few minutes and do the research on the accidents documented with the use of portable generators. These are not stories but documented facts.

If the workman on the jobsite is using a portable generator that is bonded then he would never know that the winding failed.

No assumption was made but even barefooted standing in water the touching of a properly installed meter base has no danger, but if they are wearing wet shoes and an improperly installed generator touching the meter could lead to death, documented.

No the worse case is someone who thinks that the word "safer" in some way relieves safety. Playing Russian Rolette with one bullet is safer than a fully loaded gun wouldn't you say. So let's play but you go first.

JW, I admire your tenacity and I have no argument that you are technically correct here. I have had these same arguments about these installs. I just don't know what the practical solution is here. The NEC, UL and the manufacturers need to come up with a practical solution.

 

[goldstar]

Take a few minutes and do the research on the accidents documented with the use of portable generators. These are not stories but documented facts.

If the workman on the jobsite is using a portable generator that is bonded then he would never know that the winding failed.

No assumption was made but even barefooted standing in water the touching of a properly installed meter base has no danger, but if they are wearing wet shoes and an improperly installed generator touching the meter could lead to death, documented.

No the worse case is someone who thinks that the word "safer" in some way relieves safety. Playing Russian Rolette with one bullet is safer than a fully loaded gun wouldn't you say. So let's play but you go first.

You win Mike, you're no fun anymore. But if I ever decide to play Russian Roulette I'd make sure you were there playing along with me because I know that if anyone could you'd find some obscure rule in the anals of all Code references available on the entire planet (NEC, AEC, NFPA, Plumbing codes, Building codes, International codes, NBA, PBA, medical journals, etc.) that would prevent us from ever pulling the trigger.

 

[goldstar]

The NEC, UL and the manufacturers need to come up with a practical solution.

Now there's something I can agree with.