Ground wire for 200amp service.

[Brad Baxter]

Can someone show where it says in the NEC that you can use a #6 bare copper ground wire to both ground rods. There is a argument that you must use a #4 bare copper minimum to both ground rods for a 200 amp service.

 

[C3PO]

Look at Section 250.66(A)

 

[wbalsam1]

Can someone show where it says in the NEC that you can use a #6 bare copper ground wire to both ground rods. There is a argument that you must use a #4 bare copper minimum to both ground rods for a 200 amp service.

C3PO is correct when he refers to 250.66(A). However, in my jurisdiction and that of my fellow employees, NYSEG, National Grid, Central Hudson, Rochester Gas & Electric, and all of the municipal pocos all require this ground rod grounding electrode conductor to be #4 cu. Their connection with the Public Utilities Authority permits them to surpass the NEC.

 

[Brad Baxter]

Please explain.

Please explain.

C3PO is correct when he refers to 250.66(A). However, in my jurisdiction and that of my fellow employees, NYSEG, National Grid, Central Hudson, Rochester Gas & Electric, and all of the municipal pocos all require this ground rod grounding electrode conductor to be #4 cu. Their connection with the Public Utilities Authority permits them to surpass the NEC.

OK so in other words what your saying is no matter what the NEC says that you cannot use #6 and have to use a #4 to both ground rods regardless? Why have a NEC then? or are they going to give you a NEC part 2 upgraded book for what they want?



Grounding Electrode Conductor. The grounding electrode conductor for a separate building or structure disconnecting means must terminate to the grounding terminal of the disconnecting means, and it must be sized in accordance with 250.66, based on the largest ungrounded feeder conductor.

Where the grounding electrode conductor is connected to a ground rod, that portion of the conductor that is the sole connection to the ground rod isn’t required to be larger than 6 AWG copper [250.66(A)]. Where the grounding electrode conductor is connected to a concrete-encased electrode, that portion of the conductor that is the sole connection to the concrete-encased electrode isn’t required to be larger than 4 AWG copper [250.66(B)].

 

[wbalsam1]

OK so in other words what your saying is no matter what the NEC says that you cannot use #6 and have to use a #4 to both ground rods regardless?.....

I don't know the rules around where you are. But in many, many parts of NY State, the serving utility has a charter with the Power Authority of the State of New York (PASNY). This charter is governed by the Public Utilities Commission. Somewhere any number of years ago, someone made the decision that #4 was required for grounding electrode rods. This "policy" or "rule", whichever it is, was published in all the poco bulletins and implimented by installers. Around here, it would take special permission to waive this policy/rule. You don't have to go by it, but you won't get hooked up.

....Why have a NEC then? or are they going to give you a NEC part 2 upgraded book for what they want?

Pocos talk a different language and have different concerns. They use the NESC and generally require inspectors and installers to use the NEC.

 

[C3PO]

Also in my area there are several POCO's and all of them have their own "special requirements". Some want certain kinds of straps and some only want RMC going to the meterbase.( no pvc )

It is really going to depend on where you are at. And if your POCO has a special requirement about the ground wire.

 

[Dennis Alwon]

Can someone show where it says in the NEC that you can use a #6 bare copper ground wire to both ground rods. There is a argument that you must use a #4 bare copper minimum to both ground rods for a 200 amp service.

I have never been required to run a #4 to the ground rod. It is not required by the NEC but as other have said there are higher powers than the NEC.

I will use #4 for a ufer and I do all my new homes that way. No ground rods.

 

[ultramegabob]

#4 in my area.

 

[electricmanscott]

You'd think those that require #4 would know what a waste of wire that requirement is.

 

[infinity]

You'd think those that require #4 would know what a waste of wire that requirement is.

I agree. We've never run anything larger than #6 to a ground rod.

 

[iwire]

Here a common power company requirement around pad mount transformers is four 3/4" x 10' ground rods at each corner of the pad, looped together with 4/0 bare cad welded to each rod with a 4/0 bare cad welded to the ring on each side running into the wiring compartment.

 

[c2500]

We are #4.

c2500

 

[tyha]

we just did a church that had a 200 and a 400 disconnect feeding 2 panels on the inside. the plans called for a 2/0 to building steel and a 2/0 to water pipe and a #6 to ground rod. the building was wood framed and incomming water was plastic. we placed 2 ground rods (1 at each disconnect) run a 2/0 to each disconnect from the ground rods and connected the ground rods together with 2/0 cadweld

 

[JohnJ0906]

Look at Section 250.66(A)

I agree, but I wonder if 250.64(B) plays a part in this requirement.

 

[LarryFine]

the building was wood framed and incomming water was plastic.

NEC still only requires #6 for rods, even then.

There was no footing?

 

[Buck Parrish]

Some juisdictions requirements are that if you use #4 it does not have to be physically protected. #6 would have to be sleeved (protected) down the wall.

 

[electricmanscott]

we just did a church that had a 200 and a 400 disconnect feeding 2 panels on the inside. the plans called for a 2/0 to building steel and a 2/0 to water pipe and a #6 to ground rod. the building was wood framed and incomming water was plastic. we placed 2 ground rods (1 at each disconnect) run a 2/0 to each disconnect from the ground rods and connected the ground rods together with 2/0 cadweld

Another waste of wire, Why didn't you just run the #6?? :-?

 

[Brad Baxter]

Where In The Nec?

Where In The Nec?

Some juisdictions requirements are that if you use #4 it does not have to be physically protected. #6 would have to be sleeved (protected) down the wall.

Where in the NEC does it state you need to sleeve a #6 bare copper?

 

[don_resqcapt19]

Brad,
Look at 250.64(B). It is somewhat subjective, but if you can see it is not "free from exposure to physical damage".

 

[don_resqcapt19]

It is my opinion, that other then the metering equipment and the supports for the service drop, the utility has no business specifying installation requirements on the load side of the service point. The work on the load side of the service point is covered by the NEC.