Emergency Disconnect Req’s Single Family

[C. M. Joy Company]

When installing a pedestal mounted meter main for a single family dwelling, am I required to also have an additional emergency/service disconnect mounted on the exterior of said dwelling?

 

[infinity]

Here's the code section what do you think?

230.85 Emergency Disconnects.
For one- and two-family dwelling units, all service conductors shall terminate in disconnecting means having a short-circuit current rating equal to or greater than the available fault current, installed in a readily accessible outdoor location. If more than one disconnect is provided, they shall be grouped. Each disconnect shall be one of the following:

(1) Service disconnects marked as follows:
EMERGENCY DISCONNECT,
SERVICE DISCONNECT

(2) Meter disconnects installed per 230.82(3) and marked as follows:
EMERGENCY DISCONNECT,
METER DISCONNECT,
NOT SERVICE EQUIPMENT

(3) Other listed disconnect switches or circuit breakers on the supply side of each service disconnect that are suitable for use as service equipment and marked as follows:
EMERGENCY DISCONNECT,
NOT SERVICE EQUIPMENT
Markings shall comply with 110.21(B).

 

[jaggedben]

I think not, because there are no service conductors at the dwelling.

That said, what's often overlooked is that a feeder disconnect at the house has always been required. But it doesn't have to be outside iirc.

 

[C. M. Joy Company]

I think not, because there are no service conductors at the dwelling.

That said, what's often overlooked is that a feeder disconnect at the house has always been required. But it doesn't have to be outside iirc.

Which is where my thoughts were. Now, I haven’t worked on 100’s of 10,000+ sq. ft. houses but the ones I have worked on I’ve never seen a disconnect mounted to the exterior structure of the dwelling when a pedestal type meter and disconnect have been used. I have an inspector requiring a shunt trip emergency button AT the structure if I wish to have the meter main mounted on a pedestal away from the house.

 

[jaggedben]

Can't tell from here where your sub in the building is, but 225.32 has for a very long time included the 'nearest the point of entrance' language for the disconnect. IOW, he may or may not have a point.

 

[C. M. Joy Company]

Can't tell from here where your sub in the building is, but 225.32 has for a very long time included the 'nearest the point of entrance' language for the disconnect. IOW, he may or may not have a point.

All things considered isn’t that referring to a situation where unprotected conductors are entering a building?

 

[Little Bill]

Meter/mains are allowed here as the disconnect. I think the rule is for fire fighters so they can remove power from the building/house without pulling the meter or calling the POCO. A meter/main will do just that. Doesn't make sense to me to require a shunt on the house.

 

[shortcircuit2]

2023 will require an Emergency Disconnect in your arrangement..."on or within sight" (50-feet max) see 225.41

2020 is still in effect. So there was no "in sight" rule in 2020...but be fair to the first responders and make it easy to locate

 

[C. M. Joy Company]

2023 will require an Emergency Disconnect in your arrangement..."on or within sight" (50-feet max) see 225.41

2020 is still in effect. So there was no "in sight" rule in 2020...but be fair to the first responders and make it easy to locate

Wow! Very interesting. I like the wording. It leaves less confusion for a situation such as mine. I’m completely fine with the requirements as they stand now. To make it makes perfect, logical sense as to why there should be an emergency disconnect at the exterior of a structure. I just feel as if my current installation meets those requirements. I haven’t looked at anything related to 2023 as of yet but I’ll complete code update within the next month or so. Thanks for your insight!

 

[jaggedben]

All things considered isn’t that referring to a situation where unprotected conductors are entering a building?

No, it refers to feeders.

 

[SSDriver]

Your service wires are at the pedestal. You have an emergency disconnect there and a main breaker. That is where your service wires stop.

You have NO service wires at the house.

You have a feeder going to the house. Stop looking at article 230. Look at feeder disconnect rules. 225.31 and 225.32. Shunt to service is definitely not required.

 

[shortcircuit2]

Massachusetts does have an amendment to 230.85 that permits remote control (ie Shunt) for the Emergency Disconnect. It was necessary for areas in Boston for example where service comes into the basement.

Another example of where a shunt trip would be an option is on mansions where you may have a 600, 800 or even 1200amp service. In these cases the service may come in underground to an electric room inside the dwelling. This equipment is too large to install on the outside of the dwelling.

On the shunt option for 2023 in Mass Code...the controll wires for the shunt must be in a raceway for protection.

 

[C. M. Joy Company]

Massachusetts does have an amendment to 230.85 that permits remote control (ie Shunt) for the Emergency Disconnect. It was necessary for areas in Boston for example where service comes into the basement.

Another example of where a shunt trip would be an option is on mansions where you may have a 600, 800 or even 1200amp service. In these cases the service may come in underground to an electric room inside the dwelling. This equipment is too large to install on the outside of the dwelling.

On the shunt option for 2023 in Mass Code...the controll wires for the shunt must be in a raceway for protection.

My question is that if I have my required emergency disconnect on the exterior of the house, whether it’s mounted to house itself or on a pedestal, as long as it’s terminated as a service disconnect w/ overcurrent protection. Why would I need another means of disconnect

No, it refers to feeders.

but if I installed a meter main outside why would I need to install a secondary means of disconnect inside? For all intents and purposes I could install a meter main and then run ser all of the way to the opposite side of the house to an mlo type panel. How is it different if the meter main is installed on a pedestal.

 

[C. M. Joy Company]

Massachusetts does have an amendment to 230.85 that permits remote control (ie Shunt) for the Emergency Disconnect. It was necessary for areas in Boston for example where service comes into the basement.

Another example of where a shunt trip would be an option is on mansions where you may have a 600, 800 or even 1200amp service. In these cases the service may come in underground to an electric room inside the dwelling. This equipment is too large to install on the outside of the dwelling.

On the shunt option for 2023 in Mass Code...the controll wires for the shunt must be in a raceway for protection.

But I worked at a large house in Duxbury that had a 600A underground service that came to a pedestal from the street w/ a massive disconnect and ct cabinet mounted to it. From there it went underground again to a pool house with a basement and into a MDP. From the MDP it fed the pool house , main house and guest house

 

[jaggedben]

but if I installed a meter main outside why would I need to install a secondary means of disconnect inside? For all intents and purposes I could install a meter main and then run ser all of the way to the opposite side of the house to an mlo type panel. How is it different if the meter main is installed on a pedestal.

I suppose if the pedastal is 5ft from the house, then the requirement for an additional disconnect at the house is somewhat unreasonable. But if the pedastal is 600ft away, then it's not. The way the code words it is that a separate structure requires an additional disconnect.

 

[jaggedben]

But I worked at a large house in Duxbury that had a 600A underground service that came to a pedestal from the street w/ a massive disconnect and ct cabinet mounted to it. From there it went underground again to a pool house with a basement and into a MDP. From the MDP it fed the pool house , main house and guest house

The MDP and the panel at the main house and guest house should have had main breakers. Well, the MDP could have had 6 or fewer breakers.

 

[C. M. Joy Company]

I suppose if the pedastal is 5ft from the house, then the requirement for an additional disconnect at the house is somewhat unreasonable. But if the pedastal is 600ft away, then it's not. The way the code words it is that a separate structure requires an additional disconnect.

And the pedestal itself is considered a separate structure. I appreciate your input. Thank you.

 

[kwired]

My question is that if I have my required emergency disconnect on the exterior of the house, whether it’s mounted to house itself or on a pedestal, as long as it’s terminated as a service disconnect w/ overcurrent protection. Why would I need another means of disconnect

but if I installed a meter main outside why would I need to install a secondary means of disconnect inside? For all intents and purposes I could install a meter main and then run ser all of the way to the opposite side of the house to an mlo type panel. How is it different if the meter main is installed on a pedestal.

Apparently 2023 put distance limitations from the house for the emergency disconnect.

The way it was all worded in 2020 though, that emergency disconnect didn't necessarily need to be the service disconnect. It can also be the service disconnect but doesn't always have to be.

What I don't like about the distance limitation is for typical rural services around this area, there usually is a meter/disconnect at the pole and is where firefighters here would likely go to disconnect power when they arrive but it won't always be within 50 feet of the house. Some those disconnects don't have overcurrent protection and would not qualify as a service disconnect. Everything leaving it is still service conductors, but it would still qualified as the emergency disconnect in 2020 NEC.

 

[VirutalElectrician]

Sorry for replying to an old thread....I estimated out a new build late last year and I put in an extra disconnect at the dwelling as in this rural build, the meter-main was going to be about 100 feet from the dwelling.

Researching this now, it appears that the "within 50 feet" language was dropped from the final 2023 adoption. Anyone know the history or reason why it was dropped?

Out here in rural areas, 50' isn't much....But it's certainly enough for someone to plant a tree or park a motorhome between the service disconnect and the dwelling, making it no longer in site.

 

[shortcircuit2]

Within Sight (50-feet) is in 230.85(A)(1) >>> Emergency Disco

Within Sight (50-feet) is in 225.41(A)(1) >>> Emergency Disco