Are people using #12 grounding pigtails when you pull #10's (on a 20A breaker)?

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suemarkp said:
But doesn't the box bonding pigtail require a #10 if any EGC in the box is a #10?
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My experience with this was during a NECA project in the summer of 2006, while SASCO wired a new 5-story building for CBS studios in west Los Angeles. Under the 2002 code cycle, the commercial inspector failed rough-in (no devices yet), since #12 was bonded to metal boxes with EMT & #10 wire.

The inspector did not care that EMT provides sufficient grounding & bonding, nor did he ask for plans, or know if 30A commercial kitchen equipment went on the circuit he failed. There was no code reference on failed inspection notice, just "box-bonding wire doesn't match #10".

However, the inspector missed several other shortcuts that saved the contractor money, and left me with a lasting impression that competitive bids may leverage the inspection process, which must prove code violation before cost of compliance is accrued.

Finite10 said:
Where does it allow reducing from #10 to #12 at any point in the grounding path? It does not. ..Those that do not may get a correction and have to replace the #12 prefab pigtails with #10.
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Journeymen are expected to perform, and pressing code issues during production may not be well received. Unless such code violations are recognized as costly liability, project managers are already stressed, and if the apprenticeship failed to remove an argumentative, objectionable, or disruptive character, the foremen are there to make sure that oversight is corrected.
 
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iwire said:
This is the second time posting this, care to comment on it this time?


Sure! :)
We're talking about the circuit conductor having been increased in size (for line drop or spec or whatever). In a circuit where that HAS been done you can't reduce the grounding conductor. If you increase the size, then the size has been increased. It's not talking about limiting location anywhere in the text as written. So, once it has been increased, it has been increased.

If the ungrounded conductor hasn't been increased, you never worry about it, of course. That's understood.

Where you don't use a ground, pipe ground for example, you don't worry about it Bill. Where a grounding conductor IS used, ya worry a bit.
Again, contractors are doing this. Some don't and some of those get a correction. I don?t mean to play semantic games and be a smart arse, just think I have the context understood fairly well there.
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Finite10 said:
Sure! :)
We're talking about the circuit conductor having been increased in size (for line drop or spec or whatever). In a circuit where that HAS been done you can't reduce the grounding conductor. If you increase the size, then the size has been increased. It's not talking about limiting location anywhere in the text as written. So, once it has been increased, it has been increased.

Again, contractors are doing this. Some don't and some of those get a correction. I don?t mean to play semantic games and be a smart arse, just think I have the context understood fairly well there.
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That is just plain whacko. I'm glad I don't have your inspectors.
 
Finite10 said:
iwire said:
This is the second time posting this, care to comment on it this time?


Sure! :)
We're talking about the circuit conductor having been increased in size (for line drop or spec or whatever). In a circuit where that HAS been done you can't reduce the grounding conductor. If you increase the size, then the size has been increased. It's not talking about limiting location anywhere in the text as written. So, once it has been increased, it has been increased.

If the ungrounded conductor hasn't been increased, you never worry about it, of course. That's understood.

Where you don't use a ground, pipe ground for example, you don't worry about it Bill. Where a grounding conductor IS used, ya worry a bit.
Again, contractors are doing this. Some don't and some of those get a correction. I don?t mean to play semantic games and be a smart arse, just think I have the context understood fairly well there.
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If a circuit conductor is increased for voltage drop or any other reason the EGC must also be increased proportionally. Nothing says the circuit conductor can not be reduced again at some point in the circuit as long as it doesn't get reduced to a size smaller than the minimum required at that particular point of the circut. (Don't forget taps are allowed with conditions) If that happens then there is no reason the EGC can not be reduced also. But a bonding jumper to the box would still need sized to larger conductor if it is at the point of transition to a smaller conductor. A bonding jumper to a receptacle would only need sized according to size of ungrounded conductors supplying the receptacle. If you ran 4 AWG because of voltage drop to a 20 amp receptacle, there would be nothing wrong with reducing the 4 AWG to 12 before terminating to the receptacle, the EGC could also be reduced to 12 AWG but the bonding jumper to the outlet box needs to be 4 AWG if the ungrounded 4AWG conductors are present in same outlet box. (With 4 AWG the outlet box probably will not be a 'handibox' either)
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Finite10 said:
Closest to what I'm saying.

Where does it allow reducing from #10 to #12 at any point in the grounding path? It does not.

Again, please provide the citation or exception and I'm all in.

240.4 Protection of Conductors. Conductors, other than
flexible cords, flexible cables, and fixture wires, shall beprotected against overcurrent in accordance with their ampacitiesspecified in 310.15, unless otherwise permitted or​
required in 240.4(A) through (G).

I think this covers it
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The conductors are upsized to limit voltage drop. There is no voltage drop that an electrician needs to be concerned with in a 6" length of wire. To continue to insist that any of the conductors need to remain large just because they were upsized for a distance because of voltage drop is.... just dumb.

If you don't want to listen to reason , and want to ground a 20 a circuit with a # 4 AWG , knock yourself out. I'm not going to. No one with any sense is going to.
 
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realolman said:
The conductors are upsized to limit voltage drop. There is no voltage drop that an electrician needs to be concerned with in a 6" length of wire. To continue to insist that any of the conductors need to remain large just because they were upsized for a distance because of voltage drop is.... just dumb.

If you don't want to listen to reason , and want to ground a 20 a circuit with a # 4 AWG , knock yourself out. I'm not going to. No one with any sense is going to.
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To bring this back to the realistic part of the discussion, I totally agree with what you indicated above. For that reason, it is not pratical to require a #10 pigtail to the box on a 20 amp run, even when the ground is upsized because the conductors are upsized for voltage drop. That is, however, what the concensus is here determines to be the requirement of the code.
 
Finite10 said:
We're talking about the circuit conductor having been increased in size (for line drop or spec or whatever). In a circuit where that HAS been done you can't reduce the grounding conductor. If you increase the size, then the size has been increased. It's not talking about limiting location anywhere in the text as written. So, once it has been increased, it has been increased.
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The code sections says 'where increased' not 'when increased'

In the areas they are not increased in size the section does not apply.

You seem to be struggling to read it in a way that is inconsistent with how it is written and commonsense.
 
realolman said:
The conductors are upsized to limit voltage drop. There is no voltage drop that an electrician needs to be concerned with in a 6" length of wire. To continue to insist that any of the conductors need to remain large just because they were upsized for a distance because of voltage drop is.... just dumb.

If you don't want to listen to reason , and want to ground a 20 a circuit with a # 4 AWG , knock yourself out. I'm not going to. No one with any sense is going to.
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I understand what you have to say and do not disagree with it.

Lets also look at some realities.

If you are using 4 AWG or larger conductors you will not be using 4 inch square boxes and you likely will not be using 'wire nuts' to make connections.

Chances are you are using boxes with at least one 6 inch or more dimension. To terminate equipment grounding conductors you are probably using either multiple hole lugs or a terminal bar and you bond to the box by bolting the bar or lug to the box. No need to worry if your bonding jumper is too small or not if done this way.

The fact that you will not be using 4 inch square boxes or smaller means you likely will not be installing devices so the bonding jumper to a device is not an issue either. If you need a device at this location (say a 20 amp device) you probably will have a 6 inch or larger splice box with a nipple to a smaller box to contain the device. You will splice your (probably 12 AWG) conductors for supplying the device in the 6 inch box and run to device box. In that case the ungrounded conductors are reduced in size and there is no question the grounding conductor is also allowed to be reduced proportionally.
 
kwired said:
If you are using 4 AWG or larger conductors you will not be using 4 inch square boxes and you likely will not be using 'wire nuts' to make connections.
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The OP might just surprise you.

Roger
 
kwired said:
we have veered away from those sizes but IMO still part of the topic of discussion.
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Do what????? Veered away from the specifics of a discussion on this forum, you're mistaken, that has never happened here.

Roger
 
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kwired said:
I understand what you have to say and do not disagree with it.

Lets also look at some realities.

If you are using 4 AWG or larger conductors you will not be using 4 inch square boxes and you likely will not be using 'wire nuts' to make connections.

Chances are you are using boxes with at least one 6 inch or more dimension. To terminate equipment grounding conductors you are probably using either multiple hole lugs or a terminal bar and you bond to the box by bolting the bar or lug to the box. No need to worry if your bonding jumper is too small or not if done this way.

The fact that you will not be using 4 inch square boxes or smaller means you likely will not be installing devices so the bonding jumper to a device is not an issue either. If you need a device at this location (say a 20 amp device) you probably will have a 6 inch or larger splice box with a nipple to a smaller box to contain the device. You will splice your (probably 12 AWG) conductors for supplying the device in the 6 inch box and run to device box. In that case the ungrounded conductors are reduced in size and there is no question the grounding conductor is also allowed to be reduced proportionally.
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So what is your point? This is really exasperating.

A couple folks here seem to be posting that once you upsize conductors and upsize the EGC thay it must remain upsized to the end of the circuit. That seems to me to be the whole point of the thread.

I don't agree with that.

you seem to not agree with it either, but at the same time you seem to be arguing with me.... I'm lost.
 
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realolman said:
So what is your point? This is really exasperating.

A couple folks here seem to be posting that once you upsize conductors and upsize the EGC thay it must remain upsized to the end of the circuit. That seems to me to be the whole point of the thread.

I don't agree with that.

you seem to not agree with it either, but at the same time you seem to be arguing with me.... I'm lost.
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While a couple people did either advocate that or say it. The original point of the thread seemed to be that I bring a #10 green with the #10 circuit conductors that are upsized for 20 amps due to voltage drop. Do I then need to bond to the box with a #10 or with a #12. A reasonable question. The predominate answer here and I feel the code book is yes you must use a #10. Agreed that some people think that you must then exit the box with #10, but they are wrong. If you don't need larger wire for voltage drop beyond this point you can continue with #12 hot, neutral and ground. Period. End of story.

The part that I feel the code has wrong, and I sense others agree is that there should be absolutely no problem electrically with using a #12 pigtail inside the box that is 6 inches long EVEN when you are required to use a #10 ground in the incoming conduit.


Does that make it as clear as nud?
 
I don't think that's the predominant answer here at all. I think the predominant answer here is that the pigtail can be whatever size it would be without voltage drop upsizing. It's six inches long. It's not going to cause any voltage drop. that we need to worry about.
 
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realolman said:
So what is your point? This is really exasperating.

A couple folks here seem to be posting that once you upsize conductors and upsize the EGC thay it must remain upsized to the end of the circuit. That seems to me to be the whole point of the thread.

I don't agree with that.

you seem to not agree with it either, but at the same time you seem to be arguing with me.... I'm lost.
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My point was when you are dealing with an EGC that is 4 AWG or larger that you may not necessarily have a bonding jumper to the box but rather the splicing device will be bolted to the box therefore making the bond. I know in most cases that is what I usually have. Since the OP was talking about 12 and 10 AWG it kind of is off topic a bit, but somehow we got into the case of 4 AWG grounding conductors.

My opinion is if you increase circuit conductors because of voltage drop you must increase proportionally the size of equipment grounding conductor. I don't think anyone is debating that, and it is in the code. I also see no reason why you can not reduce the circuit conductors at any point desired if it allows for desired voltage drop conditions as long as you don't reduce it smaller than minimum required ampacity of the circuit. If you reduce circuit conductors there is no reason equipment grounding conductors can not be reduced also. At very least, in the situation where we have a 20 amp circuit with 4 AWG conductors because of voltage drop, you will have to reduce conductor size before terminating on a typical 20 amp receptacle as I don't think you will find one that allows termination of 4 AWG conductors. (I will not say that I have never seen it attempted though:happysad:)
 
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