jimday
Member
- Location
- Northern California
I am currently performing an assesment of a university campus building that was built in approximately 1958. The building has 2 MV (12kV) feeders to a selector switch. The selector switch feeds 2 service transformers and main switchboards. According to the original drawings, each transformer is fuse protected via an HVL switch, at just under 250% of the transformer FLA rating. The selector switch, transformers and main switchboards are located in the locked building basement, which can be considered a a supervised location, as only university facilities shop technicians have access. According to Table 450.3(A) and the above conditions, no transformer secondary 480V protection is required. The 480V switchboards do not have main breakers and each have more than 6 feeder breakers (10 and 20 respectively). Can the HVL switches be considered as the service disconnecting means required by 230.71? I am not sure if the selector switch is load rated, but if it is can it be considered as the service disconnecting means?