Grounding a Three phase 200amp Service

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powerplay

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The Overhead Three Phase 200amp Service has over 10K fault current available, so the Disconnect Switch is before the BC Hydro Meter for the Meter Technicians safety. I Ground the Neutral at the Panel to ensure 150volts to ground from the Breakers, but is it better to connect the System Ground to the Main Disconnect Switch before the Meter?
 
Assuming you are asking about the grounding electrode conductor, 250.24 allows you to make the connection anywhere from the service point to the service disconnection means ( The utility "meter switch" is normally not consider the service disconnect)
There is one thought that the GEC should be connected close to the service point . If you follow that line of thinking, the GEC connection could be in the meter disconnect if allowed by the utility, but it does not have to be there.
 
powerplay said:
I Ground the Neutral at the Panel to ensure 150volts to ground from the Breakers,
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What do you mean by this?

but is it better to connect the System Ground to the Main Disconnect Switch before the Meter?
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Makes no difference- as Gus stated anywhere up to the service disconnect is a compliant place to wire the grounding electrode conductor. We usually connect the ground rod grounding electrode conductor to the meter base and if there are electrodes in the building then they are connected to the main panel.
 
If the disconnect is before the meter can it be considered the service disconnect? Should the main bonding jumper be in the service disconnect enclosure?
 
infinity said:
If the disconnect is before the meter can it be considered the service disconnect? Should the main bonding jumper be in the service disconnect enclosure?
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If the disconnect before the meter does not include OCPD it cannot be the service disconnect, regardless of where the service point is.
 
infinity said:
If the disconnect is before the meter can it be considered the service disconnect? Should the main bonding jumper be in the service disconnect enclosure?
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GoldDigger said:
If the disconnect before the meter does not include OCPD it cannot be the service disconnect, regardless of where the service point is.
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Seems to me to be a bit of a grey area. As far as the "meter disconnect" not have OCP, 230.91 would allow the OCP to be "immediately adjacent thereto", again a judgement call.

From previous discussions here it seems the consensus of opinions has been that the "meter disconnect" switch would not be considered service equipment for various reasons but it would have to be bonded per 250.92. IMO a bond jumper would be an acceptable means but would not suffice as the "main bonding jumper" at the actual service disconnect means.
 
I thought about "immediately adjacent" but I do not think that on the other side of the meter would qualify, regardless of the distance.
I suppose you could make that argument with a meter-main enclosure.
 
infinity said:
If the disconnect is before the meter can it be considered the service disconnect? ...
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Yes. The NEC makes no stipulation about where a meter needs to be.

I've run into a surprising number of houses configured this way. The utility distribution runs through the backyards in some places, so the service riser must be back there, and the service disconnect must be back there ("nearest the point of entrance"). But where I'm from there's usually no access between the houses, so the utility needed their meters installed street side so they could read them (before smart meters). So the arrangement is : service at back of house > service disconnecting means at back of house > meter at front of house > subpanel near meter (usually).

What gets really crazy is that most of the time the water is also at the front of the house so there's a GEC running through the whole house from the service to the water. Or in an older house the GEC is not there or is too small and it's a huge PITA to upgrade it. That scenario almost killed a couple of our jobs.

It's also confused the heck out of my crews who sometimes connect new grounding to the subpanel because it looks like the service panel, being right there next to the meter.

And yes, having the disconnect before the meter means the owner could relatively easily install distribution between the disconnect and meter without a permit and steal power. But I guess there are lots of ways to steal power if you're unscrupulous.
 
jaggedben said:
Yes. The NEC makes no stipulation about where a meter needs to be..
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No, but it does require the OCPD to be accessible so if you are in an area that the power company seals any equipment ahead of the meter and requires a disconect switch ahead of the meter that disconnect cannot be the service disconnect you would have to do this.


Utility supply > meter disconnect > meter > service disconnect > panel.
 
Well I guess thank goodness that's not the case around here because the utility and the electrical inspector would be making incompatible demands, and these houses would never have gotten electricity. :lol:
 
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