Residential Main Breaker Question

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Jerramundi

Senior Member
Location
Chicago
Occupation
Licensed Residential Electrician
@kwired Having to run the Water Meter GEC now to the outside would be a BIG ASK. That's a big change to require IMO.

To the point where it's now unreasonable.... if the purpose is truly to provide first responders with a disconnect.... you've increased the cost of the job by MORE than just adding said disconnect.

Ya know? You've effectively gone and changed the entire structure of the system just to add the disconnect. That's ridiculous, IMO.

I'm pretty that's why they've gone and explicitly allowed for CB's on the supply side.

If it's now changing the entire system by changing the location of the Service Disco, they have to allow a transitionary period, which would again, allow for CBs on the supply side.
 

kwired

Electron manager
Location
NE Nebraska
Veering in slightly different direction here, my question is how many emergency responders will use this switch? Maybe in another 20-30 years there will be enough of them installed they are common enough they figure it out. Until then they will continue what they have been doing for a long time now and that is either pulling meters or waiting for POCO to arrive, and occasionally the meter is a CT meter and won't kill power when pulled anyway.
 

Little Bill

Moderator
Staff member
Location
Tennessee NEC:2017
Occupation
Semi-Retired Electrician
@kwired Having to run the Water Meter GEC now to the outside would be a BIG ASK. That's a big change to require IMO.

To the point where it's now unreasonable.... if the purpose is truly to provide first responders with a disconnect.... you've increased the cost of the job by MORE than just adding said disconnect.

Ya know? You've effectively gone and changed the entire structure of the system just to add the disconnect. That's ridiculous, IMO.

I'm pretty that's why they've gone and explicitly allowed for CB's on the supply side.

If it's now changing the entire system by changing the location of the Service Disco, they have to allow a transitionary period, which would again, allow for CBs on the supply side.
Because you (think you) are pretty is why they allow CB on supply side? 🤔 😝
 

kwired

Electron manager
Location
NE Nebraska
CalFire told me they do not pull meters. Instead they call PG&E and wait.
I put a EPO into the design.....
I think that it has become more common nationwide to call POCO for disconnect. Probably also common to call gas utility to shut of gas as well. I think CT metering is part of reason why, not because of potential damage to metering equipment but because pulling a meter doesn't guarantee you killed all the power to the facility.

This emergency disconnect being introduced into NEC I think will not get used in many situations that it was intended for - or at least will take maybe 20 years before it does get used on more regular basis, but even then not all places will have it yet so it may be even longer before it becomes significant in emergency responders training.

I did happen to kind of witness a situation a few years ago where a vehicle crashed into a small medium voltage substation. Was a few blocks away so didn't actually see it but heard it, and we walked over to check out what was going on. First emergency person to arrive, before we even got close enough to see what happened was police officer. I was glad to see that even he was smart enough to not even get close and to keep others away. Firefighters and rescue guys all showed up but nobody got close until POCO disconnected the feed to the sub and told them it was safe to proceed.
 
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don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
I think that it has become more common nationwide to call POCO for disconnect. Probably also common to call gas utility to shut of gas as well. I think CT metering is part of reason why, not because of potential damage to metering equipment but because pulling a meter doesn't guarantee you killed all the power to the facility.

This emergency disconnect being introduced into NEC I think will not get used in many situations that it was intended for - or at least will take maybe 20 years before it does get used on more regular basis, but even then not all places will have it yet so it may be even longer before it becomes significant in emergency responders training.

I did happen to kind of witness a situation a few years ago where a vehicle crashed into a small medium voltage substation. Was a few blocks away so didn't actually see it but heard it, and we walked over to check out what was going on. First emergency person to arrive, before we even got close enough to see what happened was police officer. I was glad to see that even he was smart enough to not even get close and to keep others away. Firefighters and rescue guys all showed up but nobody got close until POCO disconnected the feed to the sub and told them it was safe to proceed.
There are already going to the meter, if they want to disconnect power before the utility gets there, so there would be little training needed to get them to open the disconnect switch in place of pulling the meter.

Also the largest electric utility in IL has installed smart meters with internal disconnects. When they are called for a fire response, they will offer to remotely open the internal disconnect.

As far as the gas supply, the common firefighter spanner tool has openings for the common gas valves and they will almost always shut off the gas at the outside meter long before the gas utility shows up.
 

hillbilly1

Senior Member
Location
North Georgia mountains
Occupation
Owner/electrical contractor
The issue is, protection from Arc Flash, even though they wear flame resistant clothing, most are not qualified to work around live parts which are exposed when the meter is pulled.
 

Barbqranch

Senior Member
Location
Arcata, CA
Occupation
Plant maintenance electrician Semi-retired
It would not surprise me if in a few years as they become even somewhat common, the fire department will list them in their property address database which will pop up when they get a call there.
 

hillbilly1

Senior Member
Location
North Georgia mountains
Occupation
Owner/electrical contractor
Everything around here except commercial, oddly enough, has the main outside since the 90’s. Most of the commercial is wired like a house, along with being all romex and non-fire rated. They just had a fire in a strip complex built like a long house, burned all four suites because of no firewalls. All wood and Sheetrock construction. Separate meters NOT grouped together with mains inside. Typical construction until we started getting inspections.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
The issue is, protection from Arc Flash, even though they wear flame resistant clothing, most are not qualified to work around live parts which are exposed when the meter is pulled.
Yes, I fully agree, but in areas with a utility response often close to an hour it is a common practice to pull the meter if they think they need the power to the inside off.
 
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