|
1 members (Scott35),
31
guests, and
28
robots. |
Key:
Admin,
Global Mod,
Mod
|
|
|
Joined: Jul 2001
Posts: 311
OP
Member
|
Is there a simple, somewhat inexpensive tester to measure ground rod resistance? I've checked my Grainger catalog and couldn't find anything.
|
|
|
|
Joined: Oct 2001
Posts: 172
Member
|
Yes there is a simple clamp on but not inexpensive over $2000. AEMC and EXTECH offer them.
|
|
|
|
Joined: Oct 2000
Posts: 4,137 Likes: 4
Member
|
Frank, I think you are going to have to define inexpensive. Watthead, The EXTECH Clamp-on is under $1400 - we sell them here in the store. There is another type they have that is under $200 Look here: https://www.electrical-contractor.net/the_store/EX/GRT_Main.htm Bill [This message has been edited by Bill Addiss (edited 08-16-2002).]
Bill
|
|
|
|
Joined: Oct 2000
Posts: 5,393
Member
|
This one goes for $113.......
|
|
|
|
Joined: Oct 2000
Posts: 4,137 Likes: 4
Member
|
Sparky, The one that you pictured is meant to measure high resistances. this one is more suitable for Ground Resistance testing. Bill
Bill
|
|
|
|
Joined: Jul 2001
Posts: 311
OP
Member
|
Thanks for the informtion. In general, a second ground rod is required to be driven only if the first is found to to have a resistance to ground greater than 25 ohms. Who usually provides the resistance test, the electrical contractor or inspector? I'm aware a lot of times the second ground rod is driven just to be done with it and not be concerned with a resistance test.
|
|
|
|
Joined: Jul 2002
Posts: 680
Member
|
Where I am in Maine 2 ground rods are driven as a matter of course. No one(at least to my knowledge) checks resistence to ground. Drive the 2 rods and be done with it. What about checking it with a copper sulfate electrode, commonly used to check cathodic protection on underground metal tanks and piping
|
|
|
|
Joined: Jul 2001
Posts: 311
OP
Member
|
walrus-
That is basically how it is done in my area. I was more curious than anything else. I thought there may of been a tester somewhere out there that was physically small and in the price range of $60.00 that was made specifically for measuring the resistance to ground of a ground rod.
|
|
|
|
Joined: Jul 2002
Posts: 680
Member
|
Frank
A copper sulfate electrode can't be that expensive? and then all you need is a 10meg ohm multimeter to check resistence. Whether or not this meets AHJ standards I have no clue. I can tell ya that soil conditions make a huge difference on how the copper sulfate elevtrode reacts.
|
|
|
|
Joined: Oct 2000
Posts: 5,393
Member
|
oops, yeah it's a megger.....
|
|
|
Posts: 4,294
Joined: December 2000
|
|
|
|
|