Multi Family dwelling service

[elec24]

Hi everyone I am new to the forum, so if this can be found somewhere I apologize. I couldn't find exactly what I am looking for. I have been asked to upgrade a 200 amp service on a 6 unit dwelling and add a house panel. I walked the job with the AHJ and he seemed fine with the set up I have listed below but I can't find anything concrete that says its a good install. This is the best setup the supply house could get me. There will be 7 disconnects and my understanding is that you cannot have more than 6 on a service. It seemed like the AHJ was fine with the main disconnect being there for the 7 meters. All of the subpanels will be in the basement.I have not done a service of this magnitude before so I want it to go smoothly. Please let me know any and all thoughts. Thank you for all of the insight.

 

[electrofelon]

It looks like the meters are cold sequenced (on the load side of the service disconnect) so there is only one service disconnect. If there is no main ahead of the meters, There is also a way to add a 7th disconnect for a house panel. See 230.40 exception #4, however it could not be grouped with the other 6.

 

[elec24]

Electrofelon,
Thank you for the quick response. That is the reason I went with the main disconnect. Its the first service of this size (6 Family dwelling) that I have upgraded and it just didn't seem quite right to me. Thank you for the clearing the air.

 

[meternerd]

Just be aware that the main disconnect will have to have be service rated and have a sealable cover, since the wiring will be un-metered. Might be best to get an OK from the utility before you buy anything expensive.

 

[kwired]

Just be aware that the main disconnect will have to have be service rated and have a sealable cover, since the wiring will be un-metered. Might be best to get an OK from the utility before you buy anything expensive.

And if that is any kind of "meter center" it probably is service rated as well as acceptable to most utilities. There typically is access to the service disconnect/overcurrent device, but not necessarily designed to gain easy access to unmetered conductors in such equipment.

Back to more direct response to OP - you are limited to six "service disconnecting means" per allowed service.

By installing such a setup you now have one service disconnecting means and seven feeders. There is no limit to how many feeders you can supply. Probably going to need a bigger main though if you were supplying say 20 dwellings instead of just 6.

 

[electrofelon]

Back to more direct response to OP - you are limited to six "service disconnecting means" per allowed service.

That is not really true. It is more accurate to say you are allowed up to six disconnecting means per set of service entrance conductors, but no more than 6 disconnects can be grouped in any one location. If you look at the code section I cited before, the OP could have a 7 disconnects.

 

[kwired]

That is not really true. It is more accurate to say you are allowed up to six disconnecting means per set of service entrance conductors, but no more than 6 disconnects can be grouped in any one location. If you look at the code section I cited before, the OP could have a 7 disconnects.

OK, with multi-occupancy applications you could run into that. With multi occupancy applications the OP possibly can have 7 service drops/laterals also as long as they each go to a different occupant space. Most of the time building construction methods will have at least 2 hour rating between each occupancy which effectively allows them to be considered separate buildings for things like this. I have even ran into situations where they make an addition to an existing facility but instead of updating the existing service a 2 hour separation (even with fire doors that automatically close) allowed to treat the addition as if it were a completely separate building. Along with that allowance though you can't supply circuits in one "building" from the other building or things like that.

 

[electrofelon]

OK, with multi-occupancy applications you could run into that. With multi occupancy applications the OP possibly can have 7 service drops/laterals also as long as they each go to a different occupant space. Most of the time building construction methods will have at least 2 hour rating between each occupancy which effectively allows them to be considered separate buildings for things like this. I have even ran into situations where they make an addition to an existing facility but instead of updating the existing service a 2 hour separation (even with fire doors that automatically close) allowed to treat the addition as if it were a completely separate building. Along with that allowance though you can't supply circuits in one "building" from the other building or things like that.

Yeah the occupancy thing from 230.40 exception 2 is a little sticky IMO. the term occupancy isnt defined so it technically comes down to the local definition which can get into fire ratings, construction specifics, and even zoning. Around here, its pretty lax and I can take any building with apartments in it, and feed each with service entrance conductors and a service disconnect in each unit (Still have to stay outside with the SEC until the point of entry though).

There are some other exceptions to 230.40 which let me get to more than 6 disconnects without getting into different occupancies, solar systems, and detached structures to a dwelling unit in particular. Actually exception #3 differentiates between "occupancy" and "multi family", allowing that exception to be used for both.

 

[elec24]

Thank you everyone for the responses. I appreciate he feedback. Here are a couple of pics of the old panels and some proposed new locations. This area is all I really have to work with in the basement, not ideal. The septic line under the old panels is forcing me to change the location of the new panels. Any thoughts?

 

[nickelec]

Looking good so far what's with all the 1900S if it's for a service receptacle I believe only one is required?

Sent from my SM-G950U using Tapatalk

 

[kwired]

Thank you everyone for the responses. I appreciate he feedback. Here are a couple of pics of the old panels and some proposed new locations. This area is all I really have to work with in the basement, not ideal. The septic line under the old panels is forcing me to change the location of the new panels. Any thoughts?View attachment 19207View attachment 19208

frame a wall in front of the septic line and mount your panels on that wall. It won't be load bearing so you don't have to be too particular on how to construct it.