Service for strip mall

Status
Not open for further replies.
George Stolz

George Stolz

Moderator
Staff member
Location
Windsor, CO NEC: 2017
Occupation
Hospital Master Electrician
Question via PM

electrictiger said:
It seems like I have a few options on this service. I wanted to get some advice as to size my wiring for parallels. I'm installing a 1200 amp disconnect and splitting that to 7- 200 amp services from a trough to 7 pvc conduits. 3 phase 4- wire for a strip mall. Can you advise me on this? Thanks!
Click to expand...

Personally, I would be inclined towards a NEMA 3R MDP, or perhaps a modular setup with a 1200A disconnect with a modular 4 stack and a three-stack. How are the tenants metered?
 
Is it an overhead service or underground. If you have underground laterals from a common point (transformer) there's a little quirk in the NEC that can save you some big $$,
For the purpose of 230.40,
Exception No. 2 only, underground sets of conductors, 1/0
AWG and larger, running to the same location and connected
together at their supply end but not connected together
at their load end shall be considered to be supplying
one service.
 
augie47 said:
Is it an overhead service or underground. If you have underground laterals from a common point (transformer) there's a little quirk in the NEC that can save you some big $$,
For the purpose of 230.40,
Exception No. 2 only, underground sets of conductors, 1/0
AWG and larger, running to the same location and connected
together at their supply end but not connected together
at their load end shall be considered to be supplying
one service.
Click to expand...

The OP is looking for 7 tenants, the exceptions only allows for 6.
 
RUWired said:
The OP is looking for 7 tenants, the exceptions only allows for 6.
Click to expand...

I don't see that limitation...but it may depend on how one reads it.... NO more than six at each location, I see, but no total on laterals from one point. Figure 230.11 in the Handbook (I know the handbook is not Code) shows a total of 24 disconnects, 6 at 4 locations,
Might be a mute point depending on load and POCO there would be limits to the one supply.
 
electrictiger said:
It seems like I have a few options on this service. I wanted to get some advice as to size my wiring for parallels. I'm installing a 1200 amp disconnect and splitting that to 7- 200 amp services from a trough to 7 pvc conduits. 3 phase 4- wire for a strip mall. Can you advise me on this? Thanks!
Click to expand...

As far as the gear I would go with a modular meter stack with a main.

But that seems to be less important than your wire sizing question.

If you go with a single service disconnect, which it seems you must with seven panels to supply and you are above 800 amps the condutors must be rated more than the 1200 amp main.

3 sets of 600 copper would do it. (420 amps each at 75 C x 3 = 1260)



Or 4 sets of 500 aluminum would do it. (310 amps each at 75C x 4 = 1240)

This assumes separate raceways for each set.
 
If you have 2-hour fire separation between the tenants, they can be considered separate buildings. If so, then the six-disconnect rule applies to each tenant.
 
Status
Not open for further replies.
Top