Main service disconnect changed to main breaker enclosure w/ breaker provision

Status
Not open for further replies.

howardrichman

Senior Member
I'm wiring a in 40 amp load for a swimming pool. The house is a large 2 story w/slab and attic. 300 amp service, both panels in 2nd floor and FULL. both 150 amp main disconnects together in garage where incoming pool line is. Question; Is it permissible to change one 150 amp disconnect enclosure to a main circuit breaker panel enclosure/ 2-4 spaces for the pool load accounting total acceptable load calculated. The only problem I see is The 4 wire service cable to the 2nd floor to the one panel would be under sized, not applicable to art. 310-15 exp, (leaving main distribution panel) and would have to be changed from a #2 ser. to a 4/0 ser.,to meet 310-16 and be very difficult. Could there be any other restrictions?

Any help Appreciated; Thank You,
HR...
 

mwm1752

Senior Member
Location
Aspen, Colo
Change out one of the 150 a garage mains to a feed thru panel with main breaker ( I am assuming the garage main is fed from the utility transformer.)
 

electricalist

Senior Member
Location
dallas tx
I doubt it's worth a load calculation to see if you are using 320 theoretical amps but if I was guessing I'd say no , not because I'm that smart but I believe house are over fed a lot of times.
I think if you could very the load you could possibly get the same money but a lot better work to re work the service and add the panel out side where the equipment can be shut off by the guy working on it.
 
Last edited:

howardrichman

Senior Member
Change out one of the 150 a garage mains to a feed thru panel with main breaker ( I am assuming the garage main is fed from the utility transformer.)

That's what I'm planning on doing, but must talk w/ inspector to find out if SER to upstairs 150 amp panel must be derated once I install a main panel w/ breaker space in garage.

HR...
 

electricalist

Senior Member
Location
dallas tx
It would not be derated exactly, but it might no longer qualify for an uprating as serving the entire dwelling load.
Thats another reason to add at the point in the system that applies the best outcome.
The panels are full --cant feed from them.
The disconnects are wired for that existing load --changing them may lead to re working the feeders.
The pool equipment will need a panel surely and best if its outside so they can have access to a disconnecting means.
If the load cant be added too after the service disxonnect----it might work before the service disconnect using a wireway and new sec taps ...load permitting and if not then a service upgrade and youre ready to go.
 

howardrichman

Senior Member
Thank you for the replies;

What I'd like to do is directly from the meter load lugs; install a main lug 2 circuit panel feeding it w/ #2 AL, and installing a 50 A breaker for the pool load. I'm not sure if I'd need a main 100A breaker in that panel. I figured the 6 switch rule w/o the main would comply. Please reply.

Thanks again for replies!
HR...
 

augie47

Moderator
Staff member
Location
Tennessee
Occupation
State Electrical Inspector (Retired)
As long as you comply with the six disconnect rule and group your service disconnects that plan will work. The inspector might ask for a load calculation to assure you don't overload the meter or service conductors
 

howardrichman

Senior Member
Thanks for reply; Job is done and came out well. All disconnects are near each other inside garage. All is pending on how the inspection goes.

HR...
 
Status
Not open for further replies.
Top