# Disconnect inside or outside building



## gpop (May 14, 2018)

Removing a over sized service to a building and running a new underground feed from a nearby mcc with a designated breaker (480v 3 phase).

Conduit will come up outside the building then punch through the wall to supply a step down transformer 480-208/120 connected to a breaker panel. There will be no other loads on the 480v side. Contractor will rewire the interior of the building. 

One argument is that 480v disconnect should be outside for emergency personnel while the other is inside due to line of sight. 

Where should it be mounted?


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## Peewee0413 (Oct 18, 2012)

Depending on what's being fed, it might be good to do line of sight. I try line of sight for things unless equipment damage odds are high. I.e. wash down as far as feed to a transformer, what's the local code say...

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## micromind (Aug 11, 2007)

gpop said:


> Removing a over sized service to a building and running a new underground feed from a nearby mcc with a designated breaker (480v 3 phase).
> 
> Conduit will come up outside the building then punch through the wall to supply a step down transformer 480-208/120 connected to a breaker panel. There will be no other loads on the 480v side. Contractor will rewire the interior of the building.
> 
> ...


Around here the disco needs to be mounted 'at the point nearest where the conductors enter the building'. 

With overhead, that's obvious.....what about underground? 

I don't know if that's NEC or local rules.


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## LGLS (Nov 10, 2007)

gpop said:


> Removing a over sized service to a building and running a new underground feed from a nearby mcc with a designated breaker (480v 3 phase).
> 
> Conduit will come up outside the building then punch through the wall to supply a step down transformer 480-208/120 connected to a breaker panel. There will be no other loads on the 480v side. Contractor will rewire the interior of the building.
> 
> ...


In the US there is absolutely no requirement for a service disconnect OUTSIDE the building if it's not residential.


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## Flyingsod (Jul 11, 2013)

For security reasons I detest an outside disconnect. Here on the west coast it’s common for a house to have its breakers outside. It’s nuts. 


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## MotoGP1199 (Aug 11, 2014)

Flyingsod said:


> For security reasons I detest an outside disconnect. Here on the west coast it’s common for a house to have its breakers outside. It’s nuts.
> 
> 
> Sent from my iPhone using Tapatalk


I agree but to be fair have you seen any issues? I haven't seen any my entire career in CA.


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