ECN Forum Forums General Topics of the Trade General Discussion Area 2 ground rods???

I just happened to be working outside today and I had a spare ground rod in my garage so I figured I would add a second ground rod to my house.

When I dug up the first ground rod, I was surprised to find that the bronze clamp on the ground rod had eroded.

Makes one think a bit doesn't it.

Here in NJ the inspectors are not only asking for 2 ground rods but the state is requireing a ground rod in the footing of new buildings. (UFER ground) This new ground rod is inspected by the building inspector on the footing inspection. There needs to be a rod in the footing 1/2" or larger and 20 feet or longer, with an approved ground lug and # 4 cu wire long enough to reach the service panel or cold water pipe.

Harold

Crlnva,

I believe it is probably just ignorance of this section of the NEC by your local authorities. As Don has already stated, the requirement to add a second rod if the first one does not measure 25 ohms or less to ground is not new. My oldest code book is a 1975 version, and its in there bigger than ever in section 250-84 (now 250.56).

The requirement for a supplemental electrode to the waterpipe has been there as long as I can remember also, and is still a requirement today. You must always install a supplemental grounding electrode in addition to the metal underground waterpipe as required in 250.53d2. It doesn't neccesarily have to be a rod, but it does have to be one of the other types listed, (ie. metal frame of the building or structure, concrete-encased, ground ring, rod or pipe, or plate).

This requirement was there in 1975 as well. It is at the end of the paragraph in section 250-81. In the 1999 code it is in section 250-50a2. I don't have my copy of the 1996 NEC here at home, but you can rest assured, its in there too.

Unless at the time VA enacted whatever version of NEC they are currently using into law, they elected to exclude these specific sections of the code, your local authorities are either ignorant of these requirements, or they have overlooked them.

[This message has been edited by Matt M (edited 12-16-2002).]

I saw a neat one today at a friend's house. The service looked very new. I don't know the name of the electrician, but WOW that was a nice job.

(My wife just shakes her head when she sees me typing stuff like that...)

What I found peculiar was that one of the ground rods was inside the house, driven on an angle. (In the basement, of course.)

I just have never heard of that before.

[This message has been edited by ThinkGood (edited 12-15-2002).]

One more question/comment re: ground rods...

I would think that the water, gas and sewer lines are near-ish to where the electric service will enter.

Do any of you "call before you dig" (or rather, sledge, pound, etc.) -- have other utilities ever been victimized by a ground rod?

I'll bet that would result in some very foul language ;-)

Thinkgood,

I was on a job many years ago and I was on the job first. I installed the ground rod for the service, got instpection, passed and the service was hooked up. I went back for the final only to find that the Gas company ripped my ground rod out of the ground, installed their gas pipe, and never told anyone. If I didn't have to go back for the final, I would never have know about it. Plus, they installed their gas meter within 3 feet of the electric meter which is a violation to the power company here in NJ. (Maybe they should have called first!)

Harold

Come to find out one of our counties require the two ground rods and the county I live in and do most of my work in, don't require it now Sometimes it's hard to determine exactly how to do a job, when different counties haven't got the same procedures. But I'm not complaining I'm reasonably sure that just one of the two ground rods I drove last week, had to have the 25 ohms requirement, I had a sore neck and arm and a broken sledge hammer to prove it