Service Disconnect Before or After Meter?

Reply

  #1  
Old 04-02-13, 07:41 PM
Member
Thread Starter
Join Date: Mar 2013
Posts: 59
Service Disconnect Before or After Meter?

I was at a friends house and noticed that the service disconnect was before the meter, can someone explain that? The equipment looked as if it hadn't been touched in over 100 years.
 
Sponsored Links
  #2  
Old 04-02-13, 08:07 PM
chandler's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Dec 2005
Location: USA
Posts: 39,968
Only the POCO can disconnect service prior to the meter. Disconnects for your house are on your side of the meter. NOW, that is unless you have a sub-meter to help with power usage programs, etc. Those meters are installed after the POCO's meter.
 
  #3  
Old 04-02-13, 08:19 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 46,045
It's extremely rare to see a disconnect before the meter.
The reason for a disconnect outside after the meter is if you require more than I thinks it's five feet of unfused wiring inside the premises.
 
  #4  
Old 04-03-13, 05:49 PM
CasualJoe's Avatar
Member
Join Date: Jan 2010
Location: USA
Posts: 9,379
It's extremely rare to see a disconnect before the meter.
The reason for a disconnect outside after the meter is if you require more than I thinks it's five feet of unfused wiring inside the premises.
I agree, it is very rare to see a residential service disconnect before the meter, but the OP did state that this was very old equipment. As Nash frequently says, all codes are local. In addition to local codes, there are the POCO rules to follow as well. When that equipment was installed, the POCO may have required a disconnect ahead of the meter. All that being said, in commercial work, a service disconnect is sometimes required ahead of the meter on 480 volt services, it's generally called cold sequence metering.
 
  #5  
Old 04-03-13, 08:04 PM
Nashkat1's Avatar
Member
Join Date: Mar 2012
Location: USA
Posts: 8,470
I've done a fair amount of commercial work. I've never installed nor serviced nor seen a disconnect on the property on the POCO side of the meter. Here, the POCOs wouldn't allow it.
 
  #6  
Old 04-04-13, 01:04 AM
Member
Thread Starter
Join Date: Mar 2013
Posts: 59
Yes confirmed. Last night I asked the super in my friends building to show me the basement again and yes, the disconnect switch is before all the meters. This is an old building, I don't know if they do it different now.
 
  #7  
Old 04-04-13, 09:42 AM
Nashkat1's Avatar
Member
Join Date: Mar 2012
Location: USA
Posts: 8,470
Having a service disconnect before tenant meters makes more sense. I think we may have done that in a couple of malls.
 
  #8  
Old 04-04-13, 06:29 PM
CasualJoe's Avatar
Member
Join Date: Jan 2010
Location: USA
Posts: 9,379
Yes confirmed. Last night I asked the super in my friends building to show me the basement again and yes, the disconnect switch is before all the meters. This is an old building, I don't know if they do it different now.
Having a service disconnect before tenant meters makes more sense. I think we may have done that in a couple of malls.
Yes, that makes a whole lot more sense now. In the very first post, you stated you were at your friend's house, I understood that to mean a single family house. If there are more than 6 meters, you'll likely find a main disconnect ahead of the meter, I often see that here too.
 
  #9  
Old 04-04-13, 06:39 PM
CasualJoe's Avatar
Member
Join Date: Jan 2010
Location: USA
Posts: 9,379
I've done a fair amount of commercial work. I've never installed nor serviced nor seen a disconnect on the property on the POCO side of the meter. Here, the POCOs wouldn't allow it.
It's a safety thing implemented in the last several years by the power company. We used to use self contained bolt-in meters on 400 amp and 600 amp services, but bolt-in meters ahead of the main disconnect are being phased out so the metering guys don't have to work those meters hot. On a single phase 400 amp service they require either a 320 socket with plug-in meter or for a full 400 amps, CTs are required.
 
  #10  
Old 04-04-13, 10:14 PM
Nashkat1's Avatar
Member
Join Date: Mar 2012
Location: USA
Posts: 8,470
It's a safety thing implemented in the last several years by the power company. We used to use self contained bolt-in meters on 400 amp and 600 amp services, but bolt-in meters ahead of the main disconnect are being phased out so the metering guys don't have to work those meters hot. On a single phase 400 amp service they require either a 320 socket with plug-in meter or for a full 400 amps, CTs are required.
Right. It made sense once he told us it was a multi-tenant space with individual metering.
 
  #11  
Old 04-05-13, 05:58 PM
CasualJoe's Avatar
Member
Join Date: Jan 2010
Location: USA
Posts: 9,379
It's a safety thing implemented in the last several years by the power company. We used to use self contained bolt-in meters on 400 amp and 600 amp services, but bolt-in meters ahead of the main disconnect are being phased out so the metering guys don't have to work those meters hot. On a single phase 400 amp service they require either a 320 socket with plug-in meter or for a full 400 amps, CTs are required.
Right. It made sense once he told us it was a multi-tenant space with individual metering.
This is on single meter installations, they call it cold sequence metering.
 
  #12  
Old 04-05-13, 06:28 PM
Nashkat1's Avatar
Member
Join Date: Mar 2012
Location: USA
Posts: 8,470
This is on single meter installations, they call it cold sequence metering.
Very interesting .
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes