Transformer Disconnecting Means (450.14)

[NCP]

Hello,

I wanted to verify article 450.14 Disconnecting means applied to my design. I'm working on a project in a manufacturing facility with tight space and I need to place a medium voltage transformer 13.8kV-480V within the building, but the disconnect switch (fault fiter) is located outside. Are there any other articles i should be looking at?

 

[Elect117]

225.52


And possibly others.

 

[NCP]

I forgot to mention this is for a generator project so this wouldn't be considered a service.

 

[Elect117]

Then 230.205 & 230.206.

It will also depend on what cycle of the NEC. There has been changes to the service disconnect section in art 230.70 (which is referenced by 230.205.

 

[PaulEd]

225.52


And possibly others.

Reconditioned equipment?

 

[PaulEd]

I forgot to mention this is for a generator project so this wouldn't be considered a service.

If the transformer opens and switches the neutral isn’t this considered a separate service?

 

[Elect117]

Reconditioned equipment?

The requirement for a building disconnect / service disconnect is separate from rules regarding reconditioned equipment. At least from my understanding.

 

[PaulEd]

The requirement for a building disconnect / service disconnect is separate from rules regarding reconditioned equipment. At least from my understanding.

I’m confused. Not sure why you brought up 225.52 then

 

[Elect117]

NEC 225 is outside feeders

225.52 is disconnecting means over 1000V.

Are you referencing 2020 NEC?

 

[PaulEd]

NEC 225 is outside feeders

225.52 is disconnecting means over 1000V.

Are you referencing 2020 NEC?

No sir. 2023

 

[Strathead]

If the transformer opens and switches the neutral isn’t this considered a separate service?

that would be a separate system, not service and 230 doesn't apply. 225 is feeders.

 

[Elect117]

No sir. 2023

For 2023 it was moved to 235.352.