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wwpirateww · Dec 30, 2006, 08:12 AM

I have a friend who want me to instal a grounding rod on his home because he said that he was showering and when his electric furnace kicked on it kicked his , almost out of the tub, now
He was tols that his home needed a grounding rod instaled to ground the house.
Existing panel didn't have a grounding rod instaled it only has a nuteral BAR no separate grond BAR?
So here's a drawing could someone please show me were the rod is connected to in the main panel?
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tkrussell · Dec 30, 2006, 08:22 AM

Just adding a ground rod is not the complete solution. Need to know what type of water system there is, such as:
City water?
Metal water pipe coming in from city water?
Well water?
Is water system in home plastic or metal?
Is there natural gas utility service in home?
Is gas system plastic or metal?
Does local code or gas utility allow, require, or disallow gas piping to be grounded?

Where is the Main Breaker?
In the panel shown in the sketch?
Or outdoor at the meter?

Grounding is very complicated and must be done correctly depending on the questions I asked.

wwpirateww · Dec 30, 2006, 08:42 AM

OK HERE GOES:
-city water? YES
-metal water pipe coming in from city water? YES
-Well water? NO
-is water system in home plastic or metal? METAL
-Is there natural gas utility service in home? YES
-Is gas system plastic or metal? METAL
-Does local code or gas utility allow, require, or disallow gas piping to be grounded? Don't think so , but DONO

-Where is the Main Breaker? Inside back wall of the home
-In the panel shown in the sketch? Yes breakers are in the main in the drawing
-Or outdoor at the meter? No meter is outside only

I tryied to answer these as best as possible THANKX for the FAST REPLY!

tkrussell · Dec 30, 2006, 09:30 AM

Originally Posted by wwpirateww

City water YES

Then this is the primary grounding electrode and must be grounded at two points, one on each side of the water meter, then add at least one ground rod outdoors, which will be the required supplemental electrode.

I say at least one because the total resistance of the entire grounding system must not exceed 25 ohms, and if it exceeds then additional ground rods must be added until the resistance of the grounding system is below 25 ohms.

City water systems are very good grounding electrodes, an usually only need the one supplemental rod.

This all can be done with one wire going from point to point, or the one wire to the water must be at least a #8 if a 100 amp panel, or a #4 if a 200 amp panel, if the wire going out to the rod is a separate wire, then it must be a in of #6

Code requires all metal piping and duct systems in a home to be bonded to the grounding system, however GAS PIPING CAN ONLY BE GROUNDED IF THE UTILITY ALLOWS CONNECTION OF A GROUNDING CONDUCTOR TO THEIR SYSTEM.
This is very important, and must confirm with the gas utility to learn their requirements.

Is there natural gas utility service in home? YES
Is gas system plastic or metal? METAL
Does local code or gas utility allow, require, or disallow gas piping to be grounded?

The grounding wires from the water pipe and the ground rod must connect to the Neutral bar in the breaker panel, because the Main Breaker is in that panel. Also, the neutral bar must be bonded to the metal nbox of the panel, using a machine screw through the bar, or a jumper wire and a lug bolted to the panel, using a machine thread screw.

Isn't this fun?

Most if not all of this is done incorrectly at your friends home, he is lucky to be still alive.

After all of this grounding is done, there still may be a fault(short) in his system, that should start tripping a breaker instead of causing the metal piping to be live with electricity.