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#118510 - 09/30/04 10:20 AM Commercial or Residential "Test" Meter Sockets
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Registered: 10/07/00
Posts: 3142
Loc: NY, USA
(submitted via Joe Tedesco)
Joe, are you familiar with "test" meter sockets? This is the second one that I have come across. The basics are that the meter clips have spring loaded contacts that come forward when the meter is pulled to provide uninterrupted service to the customer. Problem as I see it is that if the utility company serviceman is not aware of the circumstances, the service continues after a meter is pulled and the socket glassed over. Could be a real surprise for an emergency response team that thought the house was deenergized. This was a three phase that looked like it only fed the air conditioning unit, but the double lugged extra wiring extended into the garage to a sub panel with breakers. No disconnecting means at the service panel for the extra wiring.

Tom Erfert (codeenforcementguy)

Tools for Electricians:
#118511 - 10/01/04 08:49 AM Re: Commercial or Residential "Test" Meter Sockets
DougW Offline

Registered: 06/08/03
Posts: 1083
Loc: North Chicago, IL
Originally posted by Tom Erfert (codeenforcementguy:

This was a three phase...

If it was a three phase, it was probably intended that the meter never serve as a D/C - we've gotten instruction about that from our PoCo at the Fire Department. You usually see this on bigger commercial/industrial services, where the service D/C is inside, in a marked dead-front panel. On these installs, the meter reads the current, but isn't the primary flow path (Inductance read?).

Recently the PoCo (or a thoughful EC) here has started labeling the meter boxes as "NO SERVICE DISCONNECT - REMOVING METER WILL NOT SHUT OFF POWER", but the labeling has been pretty sporadic.

#118512 - 10/01/04 02:53 PM Re: Commercial or Residential "Test" Meter Sockets
iwire Offline

Registered: 01/05/03
Posts: 4343
Loc: North Attleboro, MA USA
That would be a nasty surprise.

Is it possible this type of socket is already discontinued?

Any bypass meter that I have installed works manually, you have to deliberately move a lever into bypass.
Bob Badger
Construction & Maintenance Electrician

#118513 - 10/03/04 06:38 AM Re: Commercial or Residential "Test" Meter Sockets
Dave55 Offline

Registered: 05/08/04
Posts: 666
Loc: Crystal Lake, Illinois, USA
One more reason to test for power even though it appears to be disconnected.


#118514 - 10/04/04 05:05 PM Re: Commercial or Residential "Test" Meter Sockets
codeenforcementguy Offline

Registered: 08/27/03
Posts: 30
Loc: Yuma, Arizona USA
I like that Idea of marking the panels that have the test sockets, but agree that it is a big case for always testing for voltage. The first one that I ran across was on an older commerical structure that came into question when no one knew who was paying the utility bill. The business owner rented from the city and said they were, the city PoCo said that the business was, turned out that the utility company was by default.

Make that all user's by default because I am sure the cost was passed on in some form or another.

ERFERTT > codeenforcmentguy

#118515 - 10/04/04 05:44 PM Re: Commercial or Residential "Test" Meter Sockets
Bjarney Offline

Registered: 04/10/02
Posts: 2561
Loc: West-Southern Inner-Northeast ...
Out West, EUSERC-style 125-320A manual test-bypass meter sockets are fairly large, but have embossed (paint-proof) notice: “Do not break seal—No fuses inside.”


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