Design criteria for OSW alternate power

The purpose of this project is threefold. First to provide a reliable and more continuous source of electrical power to the Operational Support Building-West (OSW) in order to better serve Mound financial and CAD computer facilities. This increased reliability shall be accomplished by the installation of a tie breaker that will connect the 480 volt secondary of the OSW substation with the 480 volt secondary of B substation, within 200 feet of the building. The OSW substation is in the penthouse of the four (4) story OSW building. The B substation is outside along the plant roadway. Installation of the tie breaker will also permit work to be done on the primary (12,470 volt) side of the transformer without a shutdown of the building. Secondly, the replacement of the OSW substation PCB transformer shall be done in order to eliminate the risk of a fire spreading PCB vapors to the building ventilation system. Thirdly, the replacement of the switchboard on the 480 volt secondary of the OSW substation with more reliable breakers. Also, the existing switches do not allow expansion of the 480 volt supply to building equipment. One of the new breakers shall supply power to a new power panel, thus providing breaker space for installation of new equipment