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Posted By: AFNB Proper system grounding of 200 A Panel - 02/19/13 09:13 PM
I want to clarify how to properly ground and install a 120/240 200A service (based on CEC code requirements). Here are two scenarios:

1) Install system grounding conductor in meter base by running properly sized copper wire from ground lug in meter base to ground rods (or ground plate). From the meter base run 2 black and one white to combination panel with main disconnect. Neutral lug is bonded to ground bar in 200 A combination panel. The system is properly grounded via the neutral wire between panel and meter base. (note that PVC pipe used between meter base and main 200A panel)

2) In house with copper water pipes install system grounding conductor in 200 A combination panel by running properly sized copper wire to water pipe (before water meter - street side) and attach using an appropriate connector. From the meter base run 2 black and one white to combination panel with main disconnect. Neutral lug is bonded to ground bar in 200 A combination panel. System is properly grounded. The meter base is also bonded to ground via the supply side neutral. (note that PVC pipe used between meter base and main 200A panel)

For any additional sub-panels you would run 2 black, 1 white and a green from the main panel to the sub-panel and disconnect bonding between the neutral bar and the ground bar in the sub-panel. This ensures the neutral does not have two separate paths to ground.

Are the two scenarios I have identified correct? I expect that local rules may be different but from my understanding this is acceptable in NB.

Please let me know.

AF, NB Canada
Posted By: dougwells Re: Proper system grounding of 200 A Panel - 02/20/13 03:23 AM
Neither would be legal that I can tell in BC.I sort of have a feeling this is a DIY question, But your profile says your an Electrician so you should know the proper way
Posted By: mikesh Re: Proper system grounding of 200 A Panel - 02/26/13 07:49 PM
AFNB
A couple of points. Single position meter bases have no provision for terminating a ground wire so that is wrong. Ground wire may only terminate on a ground lug located on the neutral buss in the main service entry section of your combo panel. It is #6 (10-812) for any service capacity under 750 volts.
The neutral lug in the meter base is allowed to be used to BOND the meter base and service equipment ahead of the main switch, not ground the service. See 10-204 and 10-624. The neutral is providing BONDING ahead of the service disconnect not grounding. This allow you to use the service neutral between the meter and the main service box to have PVC between the meter and panel without also requirming a green wire to be in the PVC raceway.
There is only 1 ground wire and it terminates in dirt at 1 end and the neutral (grounded service conductor) at the other end. So if you were to make a rule you might say grounding is done in the service box and no where else except that multi position meter bases are provided with a ground lug. Single meter bases are not.

Multi position meter bases usually do have a terminal on the neutral bus for the ground wire so it is legal to ground the service in a multi position meter base. In these cases the bonding jumper is to be installed in the service box (note this is a change in the wording of 10-624)
You are permitted to use the copper water pipe as a ground electrode but in BC we mostly install plastic water mains and frequently water service upgrades remove the grounding by replacing the copper water mains with Plastic. Use an electrode it is more reliable. New Brunswick may have copper water services as a Rule but in BC I never see copper water pipes very often except inside the buildings.
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