Background: I have replaced my 1967 era service panel. Zinsco pos to 200 amp Square D QO. Installed new ground rod directly on other side of wall below service entrance. Drove rod 7 feet and and hit rock. 20# sledge would not budge it at that point. Ground wire is run to ground bus in panel. Plan on driving another 8 ft rod six feet away down the wall. Going to drive it at an angle in hopes of getting most of the 8 feet in the ground. BTW, also covered it with a 6 inch valve cover box per somebody’s suggestion in another post.
Q1 – Original ground was via ground wire from old ground bar to cold water pipe at the washing machine connection. Maybe 16 feet of wire total, if that matters. I would not consider it the system ground now and would think that it is now simply providing a ground to the plumbing system. . Should that ground wire still be connected?
Q2 – With the panel replacement every wire/cable was long enough to reach its new termination except for the dryer (Alum 12/2 w/g). I took the opportunity to bring the dryer outlet up to code. Ran a new copper 10/3 w/g from the 30 amp breaker to a new 4 wire dryer plug and put a new 4 wire pigtail/whip on the dryer (purchased in 1991). The new pigtail was connected as follows: red to red, black to black,. white to white, and green to the ground screw on the case of the dryer (no brainer). I also kept the wire from inside the dryer connected to that ground screw as it was with the 3 wire plug. With the new 4 wire plug should that internal wire still be connected to the ground screw or taped off or what? I suspect it would be connected to the neutral.
Thanks for the help
Bill
Replies
Q1 That old ground wire would now be considered the bond to the water piping assuming it is of sufficient size (#4 for 200A I believe). In my area, the AHJ still requires this bond to be within the first 5 ft of the water pipes entrance to the building.
Q2 The bonding strap between the ground and the neutral at the dryer should be removed if you changed the pigtail to 4 wire.
Groud rod is OK being only 7 feet in the ground. I would not worry about driving another one. Just so you will know, you can also bury the ground rod horizontal if it is two feet down, which is really only easier if you have not backfilled. The ground wire should be hooked to the meter not the service panel. The neutral from the meter will of course hook to the neutral bar in the service panel which in turn is hooked to the grounding bar. that is how your grounding bar is grounded. The grounding bar and neutral bar should be bonded together. The only time it is not is when the panel is a sub panel, which i am taking that is is not in your case. The plumbing should be grounded also and to be correct with the code, if at any time pvc was used to fix something in the piping, you should remember that the grounding stops there. So any metal piping beyond that needs to be grounded. Never seen it done but that is what I was told by a inspector.
The ground wire should be hooked to the meter not the service panel.
That's not the NEC or the practice in my area.
_______________________
"I may have said the same thing before... But my explanation, I am sure, will always be different." Oscar Wilde
Bob, just south of you in KY, I had to run the ground wire from the service panel through the meter base and then to the ground rod, unbroken.
So far in three different counties with three different inspectors and three different utility companys, I have had four different instructions on how and where to run the ground wire from the service panel to the ground rod.
I now ask both the utility company and the inspector how they want it. If they differ, I have them work out a mutually acceptable design. At $55.00 per inspection and days between service connection calls, it ends up costing me both time and $$ when they don't agree.
Dave
Bob, just south of you in KY, I had to run the ground wire from the service panel through the meter base and then to the ground rod, unbroken.
So far in three different counties with three different inspectors and three different utility companys, I have had four different instructions on how and where to run the ground wire from the service panel to the ground rod.
Yeah. Amazing, isn't it?_______________________
"I may have said the same thing before... But my explanation, I am sure, will always be different." Oscar Wilde
Check out this website: http://www.codecheck.com/eleccode.htm
You could also attach an ordinary garden hose to 8 ft of pipe, and use the running water to wash out a hole deep enough for the rod. It'll wash out around any rock you hit up to about basketball size, and make a pocket that allows the rock to get pushed aside out of the way. A friend of mine used to do ground rods for TV transmitters, running 3/4" copper water pipe into the ground as much as 60 feet by this method. In that case, they just used the pipe itself as the ground rod. He also had some tricks with hammering the bottom end of the pipe flat and putting lateral holes in it.
-- J.S.
Good tip. I will remember that for next time.
I got the whole 8 ft rod pounded in on Sunday at about a 30 degree angle. I found it a bit easier to drive at an angle than straight down as I did with the first one. I ended up driving the second rod about 5 feet away from the house in order to the 6 feet distance from the first. A concrete shed foundation prohibited the original plan of attack.
It is amazing what water will cut thru isn't it.
one electrician told me if you have real hard ground if you take a spade dig a hole the depth of blade and just pore in a bucket of water and give it a minute or so to soak in and then pore in another, the ground rod will just push in.
That way is a lot less messy, and works fine if you don't hit square onto a medium or large size rock. Pumping the rod up and down helps.
-- J.S.
You could also attach an ordinary garden hose to 8 ft of pipe, and use the running water to wash out a hole deep enough for the rod.
NO. That's not kosher for a grounding rod. Bad move. At least, that's what I've been told by electricians._______________________
"I may have said the same thing before... But my explanation, I am sure, will always be different." Oscar Wilde
I can see how that would be bad for a ground rod, as you are physically removing the material the rod *needs* to be in contact with to get a low resistance.
OTOH, my plumber used a water assisted drill to remove/loosen material when putting in the new water service line. In this case, it was a good 30-35 ft run from the house to the meter. But for smaller projects, say running electric conduit under a driveway, a water powered boring device that consists of a piece of galvanized pipe hooked onto a garden hose is both cheap and effective.
> NO.
Did anybody say why? This has been done for TV transmitters and dub stages, and so far they haven't had a problem. Many of those rods check out at less than one Ohm.
-- J.S.
Did anybody say why?
Not that I recall.
_______________________
"I may have said the same thing before... But my explanation, I am sure, will always be different." Oscar Wilde