Apartment complex

[hhsting]

Please see attached sketch. I have apartment complex with building separated by firewalls Bldg 8109,8107,8105..etc. Each bldg has dewelling units.

The apartment complex shown bottom left of sketch elevation is fed from outside utility transformer to outside SWBD with 2500 main breaker. The outside switchboard has feeder breakers that feed Bldg 8109 and Bldg 8103.

Fdrs #1,#2 feed Bldg 8109 and Fdrs #4,#3 Bldg 8103 electrical room two disconnects.

The disconnects are non fused safety switch. From disconnects feeds go to meter stacks which has internal feeders to dewelling units panelboards of all the other buildings.

Questions:

1. Can bldg 8109 be feed with two feeders as shown or should it be feed with one feeder only? Same question Bldg 8103

2. The disconnect in electrical can it be fused or none fuse?

3. Overall have four total feeders should it be one feeder or can it be two feeders one feeder feed 8109 bldg and other feed 8103 bldg?


I know I had other versions of similar post earlier but they all hav one feeder to apartment complex this one has four total feeders and disconnect in electrical room right where feeders enter is non fuse. I am just really confuse how one does 225 apply here.

 

[shortcircuit2]

The 2020 NEC allows multiple feeders now....and did previously with certain restrictions.

Consult with your AHJ if the installation can be permitted per 225.30(F) with detailed plaques/directories per 225.37

Section 225.36 requires the disconnecting means to be "Suitable for Use as Service Equipment"...a non-fused safety switch would not be so rated. But, your safety switch may be required by the utility for "in sight" disconnect while servicing metering equipment.

A project this size in Massachusetts would be under "Construction Control" with engineering affidavits required per the Building Code.

The design appears to be safe if detailed plaques are provided per 225.37. First responders can shut the complex down at the outside switchboard.

 

[electrofelon]

Section 225.36 requires the disconnecting means to be "Suitable for Use as Service Equipment"...a non-fused safety switch would not be so rated.

I am not sure that is true

 

[hhsting]

We are still in NEC 2014 and Fdr#1 to Fdr#4 in post #1 sketch are going to be new and so is the switchboard outside and the utility transformer. Meter stacks are existing. AHJ does not allow plaques for new equipment I am plan review contractor of AHJ and all this this is on plans.

In post#1 sketch, Fdr #1 and Fdr#2 feed Bldg 8109 dewelling unit. Also Fdr#1 also serves bldg 8011 dwelling unit thru meter stacks in bldg 8109 and Fdr #2 also serves bldg 8107 dwelling units they meter stacks in 8109 bldg.

My concern is bldg 8109 is served by two feeders while bldg 8011 one feeder and bldg 8107 one feeder.

I am thinking So if one places by rule of 225 assuming no exception apply bldg 8109 to just have one feeder into bldg 8109 then would it comply with 225? Also then one feeder would serve multiple bldgs 8109, 8011, 8107. Not sure if that would be code compliant or not. Any thoughts? Please if anyone can help

 

[hhsting]

Igonire previous post didn’t have time to edit.

We are still in NEC 2014 and Fdr#1 to Fdr#4 in post #1 sketch are going to be new and so is the switchboard outside, non fused discos and the utility transformer. Meter stacks are existing. AHJ does not allow plaques for new equipment I am plan review contractor of AHJ and all this this is on plans.

In post#1 sketch, Fdr #1 and Fdr#2 feed Bldg 8109 dewelling unit. Also Fdr#1 also serves bldg 8011 dwelling unit thru meter stacks in bldg 8109 and Fdr #2 also serves bldg 8107 dwelling units they meter stacks in 8109 bldg.

My concern is bldg 8109 is served by two feeders while bldg 8011 one feeder and bldg 8107 one feeder.

I am thinking So if one places by rule of 225 assuming no exception apply bldg 8109 to just have one feeder into bldg 8109 then would it comply with 225? Also then one feeder would serve multiple bldgs 8109, 8011, 8107. Not sure if that would be code compliant or not.

Also Fdr#3 and Fdr#4 supply thru meter stacks bldg 8103. Also Fdr #3 supply bldg 8105 and Fdr #4 supply 8101. Bldg 8101 has one Fdr supply Fdr #4 , Bldg 8105 one Fdr supply Fdr #3 but Bldgs 8103 supply by two fdrs Fdrs #3,#4.

I am thinking So if one places by rule of 225 assuming no exception apply bldg 8103 to just have one feeder into bldg 8103 then would it comply with 225? Also then one feeder would serve multiple bldgs 8103, 8015, 8101. Not sure if that would be code compliant or not

But then Keats say Bldg 8103 is supplied by one Fdr and bldg 8109 is supplied by one feeder would overall apartment complex be counted as one structure and then still not comply with 225 or one can count individual bldgs not look at overall structure?

Any thoughts? Please if anyone can help

 

[electrofelon]

The general rule is only one feeder can serve a building. There are some exceptions.

There is nothing that says a feeder can't supply more than one building.

No you can't count a multiple building complex as one structure. Why would you even think that?

 

[hhsting]

The general rule is only one feeder can serve a building. There are some exceptions.

There is nothing that says a feeder can't supply more than one building.

No you can't count a multiple building complex as one structure. Why would you even think that?

I really don’t know but plans call it cluster

 

[hhsting]

Post #1 attachment Fdr#1 to Fdr #4 I am wondering if one can calculate load of feeder using optional methods NEC 2014 section 220.84(A)? 220.84(A)(1) Each dewelling unit has electric cooking equipment, 220.84(A)(2) each dewelling unit has electric HVAC.

Only part I am confused on is each 220.84(3) dewelling unit is supplied by one feeder only because from meter stacks each dewelling unit is supplied by one feeder however Fdr#1 to Fdr#4 is supply multiple dwelling units.