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Matthew Barnicle
08-21-2009, 12:19 PM
Inspected a home with the following:
2 main disconnects to shut power off to the home, one was to the service equipment in a utility room, the other was to a small disconnect breaker panel feeding the a/c equipment located outside next to the meter. Both of these panels were fed directly from the meter base.
Assuming (and there are many assumptions here)
1) the meter base is rated for multiple taps (meter box is sealed and can not be inspected).
2) the disconnect for the a/c equipment is rated for service equipment

Would this be acceptable?
It is less than 6 throws to disconnect main power, but in two locations. The homeowner would have to turn off one breaker, go outside and around the corner of the house to shut off the 2nd. Not ideal, but are the two locations acceptable?

A.D. Miller
08-21-2009, 12:38 PM
Inspected a home with the following:
2 main disconnects to shut power off to the home, one was to the service equipment in a utility room, the other was to a small disconnect breaker panel feeding the a/c equipment located outside next to the meter. Both of these panels were fed directly from the meter base.
Assuming (and there are many assumptions here)
1) the meter base is rated for multiple taps (meter box is sealed and can not be inspected).
2) the disconnect for the a/c equipment is rated for service equipment

Would this be acceptable?
It is less than 6 throws to disconnect main power, but in two locations. The homeowner would have to turn off one breaker, go outside and around the corner of the house to shut off the 2nd. Not ideal, but are the two locations acceptable?

MB:

230.71 Maximum Number of Disconnects.
(A) General. The service disconnecting means for each service permitted by 230.2, or for each set of service-entrance conductors permitted by 230.40, Exception No. 1, 3, 4, or 5, shall consist of not more than six switches or sets of circuit breakers, or a combination of not more than six switches and sets of circuit breakers, mounted in a single enclosure, in a group of separate enclosures, or in or on a switchboard. There shall be not more than six sets of disconnects per service grouped in any one location.

Jerry Peck
08-21-2009, 12:56 PM
Would this be acceptable?


No, they would both need to be grouped in the same location.

Aaron posted part of the applicable code, here is the rest.

- 230.72 Grouping of Disconnects.
- - (A) General. The two to six disconnects as permitted in 230.71 shall be grouped. Each disconnect shall be marked to indicate the load served.
- - - Exception: One of the two to six service disconnecting means permitted in 230.71, where used only for a water pump also intended to provide fire protection, shall be permitted to be located remote from the other disconnecting means.
- - (B) Additional Service Disconnecting Means. The one or more additional service disconnecting means for fire pumps, emergency systems, legally required standby, or optional standby services permitted by 230.2 shall be installed remote from the one to six service disconnecting means for normal service to minimize the possibility of simultaneous interruption of supply.
- - (C) Access to Occupants. In a multiple-occupancy building, each occupant shall have access to the occupant’s service disconnecting means.
- - - Exception: In a multiple-occupancy building where electric service and electrical maintenance are provided by the building management and where these are under continuous building management supervision, the service disconnecting means supplying more than one occupancy shall be permitted to be accessible to authorized management personnel only.

Eric Barker
08-21-2009, 05:43 PM
As far as I know, the meter panel is exclusively for the SEC. Any other wiring or circuit pass through it is wrong.

Jerry Peck
08-21-2009, 06:03 PM
As far as I know, the meter panel is exclusively for the SEC. Any other wiring or circuit pass through it is wrong.


Eric,

Yes and maybe.

Yes, you are correct that no other conductors are allowed to be in the same enclosure with the service entrance conductors, and that the meter pedestal is only for the underground service lateral come up to the meter and the service entrance conductors go out to the service equipment.

I forgot to ask: Where does that conduit go/come from? I only see it entering/leaving, and that might not be good at all.

Maybe ... the ones I've seen have a divider (grounded metal divider) which separates the meter space from the open space below which the service lateral conduit runs through, terminating into the bottom divider, which means that space down below the divider is not exposed to the underground service laterals, but is just open space and the cabinet serves to protect the conduit riser from physical damage.

If that last part is the case there, I am not sure that is a definite "No.".

Hopefully Peter will respond as I am sure he knows more about those than I do.

Jerry Peck
08-21-2009, 06:23 PM
The one I found on the internet does not have that divider ( http://www.wisconsinpublicservice.com/service/sm/sm2_index.pdf m scroll to see section drawing) and the underground service lateral conduit simply terminates in the open area below the meter, thus no other wiring would be allowed to go through there.

So maybe I am just imagining having seen that bottom divider and the conduit terminating into it????

Robert Mattison
08-23-2009, 10:31 AM
Jerry, there is a divider, if the service lateral cable comes up from the bottom.

Milbank has single meter socket rated for service used with intall 100 amp.
2-pole breaker. The picture I pull up clearly shows a divider to seperate
the Line side conductors from the Load side conductors.:cool:

Jerry Peck
08-23-2009, 12:50 PM
Jerry, there is a divider, if the service lateral cable comes up from the bottom.

Milbank has single meter socket rated for service used with intall 100 amp.
2-pole breaker. The picture I pull up clearly shows a divider to seperate
the Line side conductors from the Load side conductors.:cool:

Robert,

Except that Eric showed a meter socket only pedestal, not a service pedestal with meter socket and service equipment.

Robert Mattison
08-23-2009, 03:37 PM
Eric Barker

quote: "As far as I know, the meter panel is exclusively for the SEC. Any
other wiring or passing through is wrong."

So in the picture, you know that there a wire or circuit passing thru this
meter. I only see a conduit running out on the left side. With that being
said I will tell you something, in my State the Power Company sets the
the rules for meter panels.

Example: Central VT. Public Service offer a RATE 11
The meter is set up to offer two different rates, (so much per
kwH) Inside one of there supply electrica meter is a set of
dry contacts. The customer may chose to use the contacts
to turn of his electric heat. So he not paying the higher rate
when the electric heat is on. Its usually for 4 hours at a time.
And they set up to peak usuage in the morning and in the even-
ing.

The electrician run a piece of 12-2 UF cable into the meter
panel. Then the Meter Man attach a quick connect pigtail
to it, and plug it into the meter panel, dry contacts circuit.

The wire, switch loop may also be run in conduit with thhn.thwn
wire inside it.

So from where stand I say the answer is no. But only the power com-
decides what else get into the meter panel.:cool:

Bill Kriegh
08-23-2009, 04:12 PM
A meter doesn't necessarily need to be rated for multiple taps to have multiple disconnects fed from it. There is often enough room in the enclosure for any of a number of different types of connector that would allow tapping the load side wires. The insulated multi tap and gutter type connectors are examples. They allow a good mechanical splice and don't eat up a lot of space in the enclosure.

Bare tap splices of various kinds are also OK but the splicing compound and tape necessary to insulate them as well as the limited working space make them less desirable, at least IMHO.

Some utilities are a bit fussy about the things in a meter can and some don't pay much attention as long as the riser wires or lateral is untouched pre-meter.

All, of course, here for info as the remote disconnect busts the OP's installation.