ground electrode

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lou32

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I'm an electrician in Tx, I'm doing a meter loop upgrade I'm using the grounding electrode system using art. 250.50 the only electrode system present at this time is only a ground rod. According to ART. 250.53 (a), ART. 250.53(g) it will comply with the minimun stadards of the 2005 NEC if I use the rod system again. Now according to the AHJ he says that I need to use two ground rods to meet this ART. and pass the elecrtical inspection. I will appr. all input Thank You.
 
Two ground rods is the cheapest, simplest way to comply with Article 250. I agree with the inspector.
 
Well, I asked him if he had a rod tester or a megger that prove that the new rod did not meet the ohm req. and his answer was No I don't but he said that some where in the NEC that I need two rod no matter what. I then asked him the art . or sectios in the code and could not give the answer.
 
if the g-rod is only ground, then I would run 2- 3/4x10'. I had a AHJ require a third one and they were in a tri-angle.

A lot of guys will tell ya only to use one since that meets code, but code is only the min. req.

edit to add: I wouldn't even bother him to fight it, its 1 g-rod and its for a good cause IMO
 
Drive the second rod, and be done with it. By time you get a 3-point earth ground resistance test set, get up to snuff on utilizing the meter and properly perform the test you could drive 10 rods and still be financially ahead of the game.
 
SiddMartin said:
if the g-rod is only ground, then I would run 2- 3/4x10'. I had a AHJ require a third one and they were in a tri-angle.
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Neither the two 3/4" X 10' rods or three rods are ever required to meet the requirements of Article 250.
 
I think if I have use a system recognize by the code and did it with the intent of the code.I also think I'm not violatng code (NEC) remember the new rod is the only elect. system present ,,I would not have a problem if it was a local ord. Cause the state of texas does not req. it.
 
SiddMartin said:
if the g-rod is only ground, then I would run 2- 3/4x10'.
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Why would you use 3/4 x 10, do you think it really makes a difference when you are only connecting a #6 to it?

SiddMartin said:
A lot of guys will tell ya only to use one since that meets code, but code is only the min. req.
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It only meets code if it is 25 ohms or less.

SiddMartin said:
edit to add: I wouldn't even bother him to fight it, its 1 g-rod and its for a good cause IMO
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Well, I don't really think it's a good cause, it's more of a placebo but, I agree that in most cases it's not worth proving the 25 ohms or the fight considering the price of an 8 foot galvanized rod.

Roger
 
Well , I still added the 2nd rod like you said just get it over wit. but what bother me is that he told me I was violating the code an if 2 rod to meet Art. 250
 
roger said:
Why would you use 3/4 x 10, do you think it really makes a difference when you are only connecting a #6 to it?

It only meets code if it is 25 ohms or less.

Well, I don't really think it's a good cause, it's more of a placebo but, I agree that in most cases it's not worth proving the 25 ohms or the fight considering the price of an 8 foot galvanized rod.

Roger
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I understand your point, the AHJ I had said he wanted 3 instead of 2. I said "no problem". I have learned to pick my battles.
 
lou32 said:
Well, I asked him if he had a rod tester or a megger that prove that the new rod did not meet the ohm req. and his answer was No I don't but he said that some where in the NEC that I need two rod no matter what. I then asked him the art . or sectios in the code and could not give the answer.
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I think proving the rod has 25 ohm's or less is up to you not the inspector. So you really are not in compliance with the code if you don't have the second ground rod.
 
lou32 said:
I'm an electrician in Tx, I'm doing a meter loop upgrade I'm using the grounding electrode system using art. 250.50 the only electrode system present at this time is only a ground rod. According to ART. 250.53 (a), ART. 250.53(g) it will comply with the minimun stadards of the 2005 NEC if I use the rod system again. Now according to the AHJ he says that I need to use two ground rods to meet this ART. and pass the elecrtical inspection. I will appr. all input Thank You.
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The code require to install another ground rod if the measured resistance is above 25 ohms. You are not violating the code since you have complied its minimum requirement but there are AHJ that inspects our electrical installation and certifies that it is safe and complied the code and also the local ordinances. But you said it is not a requirement in Texas, still the AHJ has this power and authority to implement above the code for public safety.
 
acrwc10 said:
I think proving the rod has 25 ohm's or less is up to you not the inspector. So you really are not in compliance with the code if you don't have the second ground rod.
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Where in the code states that you are not compliance if you only have one ground rod as grounding electrode? I believe the code only require the additional ground rod for more than 25 ohms measured resistance on the single ground rod.

As what sir infinity said that two ground rod is the simplest grounding electrode system but it doesn't mean that a single ground rod is a violation in the code. Two ground rod is better than one because of combined lower resistance.
 
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Out Topic,

What would be the size of the GEC for single ground rod as grounding electrode and for two ground rod installation? Also, what is the size of the jumper between the two ground rods?
 
enteng14 said:
But you said it is not a requirement in Texas, still the AHJ has this power and authority to implement above the code for public safety.
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This is not true around here. The adopted version of the NEC is what the inspector is required to follow by law. He can't simply enforce whatever he feels like enforcing.

enteng14 said:
Where in the code states that you are not compliance if you only have one ground rod as grounding electrode? I believe the code only require the additional ground rod for more than 25 ohms measured resistance on the single ground rod.

As what sir infinity said that two ground rod is the simplest grounding electrode system but it doesn't mean that a single ground rod is a violation in the code. Two ground rod is better than one because of combined lower resistance.
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Article 250 requires that the rod have a resistance of 25 ohms or less or it must be augmented by another rod or electrode. If you don't want to actually test the single rod you'll need to install a second one. The largest conductor required to the rod is #6. A second conductor can be jumped to a second rod 6' or more away which is also required to be no larger than a #6.

250.56 Resistance of Rod, Pipe, and Plate Electrodes.
A single electrode consisting of a rod, pipe, or plate that does not have a resistance to ground of 25 ohms or less shall be augmented by one additional electrode of any of the types specified by 250.52(A)(4) through (A)(8). Where multiple rod, pipe, or plate electrodes are installed to meet the requirements of this section, they shall not be less than 1.8 m (6 ft) apart.
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