Ask Me Help Desk - Square D load center ground bar?

Square D load center ground bar??

I am installing a new load center and purchased a SquareD Home line box with a 200amp breaker. Service enters the house through a SquareD meter base that also has a 200amp main breaker. The meter base is attached to a single ground rod aprox 8 feet away. The new load center does not have separate ground bars and so I purchased a set but do not see any place to attach them. Should I drill and tap the box to connect the ground bars to the load center or just forget the whole thing and use the neurtal for the ground. Also, my understanding is that the load center should not be bonded. Is that correct? Thanks

Quote:

Originally Posted by inprimer

The new load center does not have seperate ground bars and so I purchased a set but do not see any place to attach them.

For real?

EVERY Square D panel I have ever installed has had provisions for mounting accessory ground bars.
There should be a hole, or holes, with raised nubs in line with them. This is where you mount the ground bars.

Thanks, I'll look at the panel again in the morning. Am I correct in my belief that the load center should not be bonded?

In your case the Neutrals and grounds should be separate because the bond is done at the 200 A breaker in the meter base.

You do need to bond copper plumbing though if that's not done already.

Someone help me on the rules: It's within x' after it enters the house and with #y AWG wire. I forget what z and y are. 5' for x? #6 for wire?

What?

Quote:

Originally Posted by KeepItSimpleStupid

Someone help me on the rules: It's within x' after it enters the house and with #y AWG wire. I forget what z and y are. 5' for x?, #6 for wire?

KISS should mean simple, can you express your question in simple english?

Inprimer, did the instructions come with the ground bar?

I am sure if you take the ground bar and look at the inside back of the panel, you will find machine screw threaded holes that will math up with mounting holes on the ground bar.

Thanks for the help. I found the attach points this morning. It helps to have some light on the subject. One more thing. Is one ground rod sufficient? I have been told two are required in some areas.

Code requires one rod, and more as necessary to reduce ground resistance to 25 ohms or less.

State of Maine Electrical Inspector requires two rods, at least, then more if needed.

So, best to check with your local or state code to learn what is required in your area.

Ground rods, when more than one, must be no closer than six feet apart.

OK:

Fill in the blanks:

A copper plumbing system should be bonded to the electrical system with #_____ wire within ____ feet of entering the house. The wire can be a) Solid, b) Stranded, c) both; A) insulated, B) uninsulated or C) both and green if uninsulated

Thanks.

If you have to run 30' of wire to get there, so be it.

Quote:

Originally Posted by KeepItSimpleStupid

OK:

Fill in the blanks:

A copper plumbing system should be bonded to the electrical system with #(Depends on the size of the service entrance conductor. Typically #8cu for 100A and #4cu for 200A) wire within 5 feet of entering the house if this connection is to be used as a pipe grounding electrode. If this is simply a water bond there is NO limit as to distance as long as the connection is accessible. The wire can be a) Solid, b) Stranded, c) either; A) insulated, B) uninsulated or C) both and green if uninsulated. Bare or insulated. Any color is fine, green is NOT required.

Thanks.

If you have to run 30' of wire to get there, so be it.

...

Ok, thanx, question is much clearer, however, it is muddled, combines two different aspects of grounding, grounding and bonding. Allow me to attempt to explain this. I am sure I will be confusing.

Each separate structure that has electric service supplying power, the neutral in that service disconnecting means must be grounded to an approved grounding electrode, grounding the neutral and equipment ground to earth.

This grounding connection may be at the enclosure containing the Main Service Disconnecting Means, OR at the utility meter, OR at the transformer, or at all of these locations. Typically, it is done at the Main Panel, often done at the meter. Never done after the Main Panel, as from this point on the neutral must be kept separated. This is the location that the neutral is BONDED to the equipment ground, and after the Main, again separated from the neutral.

Generally speaking, most homes, I believe, will be located in a city, and/or served by a public water utility that uses a metal water line into the home.

If a building is served by a buried metal water line, AND, that metal water line is in contact with earth 10 feet or more, IT SHALL be the primary grounding electrode, AND it shall be supplemented by a min 8 foot ground rod driven in the earth.

Any grounding electrode conductor connecting to a metal water pipe being used as a grounding electrode shall only connect within the first 5 feet of the exposed pipe.

The size of the grounding electrode conductor (GEC) shall be determined by NEC Table 250.66, which will refer to the size of service entrance conductors (SEC). A 100 amp service typically will use a #2 aluminum, and a 200 Amp service will use a #4/0 aluminum.

Table 250.66 lists a #8 Cu or # 6 Al GEC for a service using a #2 SEC and a #4 Cu or a #2 Al for a service using #4/0 SEC.

By using this buried metal water line as an electrode automatically BONDS the interior metal water piping system, and assumes the entire water system in the building is metal.

If a structure is served by a non-metallic water line, the neutral/equipment ground shall be grounded to earth using other approved grounding electrodes, the typical being a ground rod. The size of the GEC is the same as above.

If the interior water system is metal, IT SHALL BE BONDED to the neutral/equipment ground connection at the service, or any equipment grounding termination in a panel. Again, this BONDING conductor shall be sized according to Table 250.66.

So, hopefully, now you can see that your question combined answers from both grounding and bonding.