Grounding on a residential service

[Doctor Electric]

My apprentice is argueing that we can run a #4 ground to the water main from the panel and in the middle of that run. Irreversible crimp on a #6 ground and run that to the 2 ground rods outside please give me some help guys ive always known one ground to the rods from the main electrical panel and one ground to the water main from the main electrical panel. Idon't have my book with me today....

 

[infinity]

You need to more closely look at the terminology to sort out the confusion, the ground to the water pipe is a GEC. It is permissible to tap the GEC to connect to other electrodes. The tap is a bonding jumper and can be connected to the GEC by a split bolt because bonding jumper connections are not required to be irreversible. You apprentice almost had it right.

 

[Doctor Electric]

Wow im dumbfounded. Why have i always been taught two separate grounds?

 

[electrofelon]

Wow im dumbfounded. Why have i always been taught two separate grounds?

Most of the "code" you hear from other people or at the supply house counter is completely wrong.

 

[tom baker]

For example look of the definition ground in article 100.

 

[roger]

Wow im dumbfounded. Why have i always been taught two separate grounds?

As Electrofelon said, you weren't learning from the code book.

 

[busman]

Please correct me if I'm wrong, but I thought GEC taps were for multiple disconnects in separate enclosures (250.64(D) - NEC 2014). I think a better way to look at it is that the GES needs to be all connected together with listed means, but does not require exothermic welding or irreversible connections. The one GEC from the Disconnect to the GES has to be continuous or use exothermic welding or irreversible connections if it is spliced. Do I have that right?

Mark

 

[infinity]

Please correct me if I'm wrong, but I thought GEC taps were for multiple disconnects in separate enclosures (250.64(D) - NEC 2014). I think a better way to look at it is that the GES needs to be all connected together with listed means, but does not require exothermic welding or irreversible connections. The one GEC from the Disconnect to the GES has to be continuous or use exothermic welding or irreversible connections if it is spliced. Do I have that right?

Mark

Yes you're correct. Once you identify the conductor function (GEC or bonding jumper) that will dictate whether an irreversible or a listed non-irreversible connector is required.

 

[suemarkp]

I see an assumption that the #4 to the water pipe is a GEC. It may or may not be. Does that water pipe extend into the earth for 10' or more, is it metal, and are you attaching that #4 within 5' of where the water pipe enters the building? If not, you're just bonding the water and that wire isn't a GEC, so it would need an irreversible splice to turn it in to a ground electrode.

At my house I ran an unbroken #4 from the panel to the ground rods and split bolt on a #4 tap to the water pipe (which was just a bond and not a ground electrode, but it could have been split bolted in either case).