BVR set up computer Easy Power software to model the 12.47kV loop from Facility bus to include line impedances and detailed breaker/protective relay information. Additionally set-up the Easy Power software to model the 480 volt distribution system from the 12.47kV side of the transformers, to the six 480 volt main breakers and then to all of the distribution boards, panels and 5 HP or higher rated motors. Included in the model are the impedances of the 12.47kV to 480 volt transformers, the impedances of the cable/conduit runs from the main 480 volt switchgear to the 480 volt switchboards and the impedances of the cable/conduit runs from the distribution boards to any distribution panels fed off of the distribution boards.
Also modeled all motor loads connected to the distribution panels and the detailed characteristics of all main drawout breakers, and main molded case circuit breakers in the distribution boards and panels. The continuous and AIC ratings of the 480 volt main switchgear and all distribution boards and panels are also included in the model. BVR also prepared the short circuit calculations, protective coordination study, and arc flash study for the 12.47kV loop and for the 480 volt distribution system. As a Result the facility was able to greatly expand its operational capabilities as well as increase safety for its workers.
