EGC

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Alwayslearningelec

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Schedule shows a separate ground wire and should obviously be priced that way but technically could one not install that conductor and use the EMT as the EGC?

What would determine whether one would do that? Thanks.
 

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infinity said:
Your EGC in each set is is much too small. In fact with 250.122(B) and up sizing for 24 sets using a wire type EGC is not practicable.
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But what about "A" that says "in no case shall they be required to be larger than the circuit conductors supplying the equipment"?
 
steve66 said:
But what about "A" that says "in no case shall they be required to be larger than the circuit conductors supplying the equipment"?
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The circuit conductors are 24 parallel sets of 600 kcmil or 14400 kcmil not 600 kcmil.
 
infinity said:
The code section is right there in post #5.
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So the increase in size section, got it.

So the ungrounded conductors have obviously been increased.
Now the wire type EGC must be increased in size proportionally.
That's the math I don't follow?

BTW, it does say increased in size. The # of sets are really increased not the size. ??
 
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horsegoer said:
So the increase in size section, got it.

So the ungrounded conductors have obviously been increased.
Now the wire type EGC must be increased in size proportionally.
That's the math I don't follow?

BTW, it does say increased in size. The # of sets are really increased not the size. ??
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600*10=6000 kcmil increased to 600*24=14400 kcmil. That's a factor of 2.4. 500 kcmil*2.4=1250 kcmil
 
infinity said:
The circuit conductors are 24 parallel sets of 600 kcmil or 14400 kcmil not 600 kcmil.
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I'm not sure I agree with your interpretation. It says the ground wire doesn't have to be any larger than the circuit conductors. A conductor is a conductor, not the equivalent size of a group of parallel conductors.

Besides, how would the ground wire ever get larger than the equivalent area of the parallel conductors? For the example we are looking at, there isn't any way the ground wire would have to be larger than 14400 kcmil, so it would be a useless exception.
 
steve66 said:
I'm not sure I agree with your interpretation. It says the ground wire doesn't have to be any larger than the circuit conductors. A conductor is a conductor, not the equivalent size of a group of parallel conductors
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The interpretation is correct. If you had 10 sets of #3/0 for a 2000 amp feeder the minimum size EGC is 250 kcmil. You cannot use a #3/0 EGC just because you chose #3/0 as the ungrounded conductor size.
 
Clarify.... The are calling for 24 sets of 600CU on a 4000 amp feeder ??
Any idea why ?
 
infinity said:
The interpretation is correct. If you had 10 sets of #3/0 for a 2000 amp feeder the minimum size EGC is 250 kcmil. You cannot use a #3/0 EGC just because you chose #3/0 as the ungrounded conductor size.
Click to expand...

Well, right about 6 min and 30 sec, Mike says the equipment grounding conductor doesn't have to be larger than the phase conductor. But right about the end, someone else says the grounding conductor may have to be large than the phase conductors, then there seems to be some discussion about what actually got put in the code right as the video ends.

So I don't think its cut and dry by any means. To me it says what it says, and it says it doesn't have to be larger than the phase conductors "in any case".

https://www.bing.com/videos/search?...C7529AE1AEE13B91CDEBC7529AE1AEE13&FORM=WRVORC
 
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