Power and CPT Transformers - Inside or outside of building enclosure

[rockman7892]

We are involved in a lot of projects that involve new electrical rooms in elevated IPA buildings that usually have a need for either a power transformer or a large CPT transformer (for station power) located either inside or outside of the building to support the new distribution equipment content in the building.

I have seen this proposed both ways with some proposing oil-filled units located outside of the new building while others propose dry-type units located inside of the building. Obviously there are things to consider here in terms of available area inside/outside of building, installation cots, etc...

In general is there a standard approach or practice on location of transformers relative to the new building? Most of the power transformers i'm referring to here are 1000+ KVA units with MV primary and LV 480V secondary. Most CPT's are 75kVA + units for MV to 120V control power.

 

[cuky2000]

Not sure if your post is clear to me regarding the transformer capacity of MV CPT for 1000+kVA, MV/120V?.

If is an option to specify a pad-mounted unit see either the links for oil-filled (outdoor) or dry-type(indoor & outdoor) applications.

 

[prc]

If for indoor use, either dry type or ester filled units are preferred. But if the transformer is very near to people( eg Olympic stadiums) dry type is the choice. Oil filled is economical if the transformer is away from buildings/ people and can handle the fire in the event of a fire,