I am working on specifying a transformer for a building on a college campus with a 12.47kv loop. I am trying to size the secondary OCP for a 300kva transformer with a 480V secondary. I am questioning if the transformer would fall into the category of supervised or unsupervised per 450.3(A). My hope was to use a 600A disconnect on the secondary but this does not fall within the 125% requirement of an unsupervised location. The college owns and operates their own loop and has their own electrical staff for maintenance so I am inclined to believe that it falls within the following definition : "A supervised location is a location where conditions of maintenance and supervision ensure that only qualified persons monitor and service the transformer installation."
Supervised vs Unsupervised Location of Transformer
- Thread starter WisMitch
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