ARCHIVED REPORTS LEC APPLICATION FOR CERTIFICATION

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® WorleyParsons resources&energy 4.11 Medium Voltage Motor Controllers The medium voltage motor controller lineup will be rated 4.16kV nominal, three-phase, three-wire with bus ratings not to exceed 1200 amps continuous and 250MVA fault current duty. The MV MCC will be NEMA Class E2 rated equipment. The MV MCC will be double high construction and drawout where possible. The MV MCC will contain vacuum and control power will be via an internal control power transformer. All motor controllers will be controlled from the DCS. The medium voltage motor controller lineup will consist of motor controllers and a main load-break switch. The 4160V medium voltage controllers will be rated 4.16V nominal, three-phase, three- wire switchgear with ratings not to exceed 3000A continuous and 50kA fault current duty. The MV controllers switchgear will be sub-fed by the main 4.16kV switchgear through a cable connection. 4.12 Low Voltage Switchgear The low voltage switchgear will be rated 480V nominal, three-phase, three-wire with ratings not to exceed 4000 amps continuous and 100 kA fault current duty. The low voltage switchgear will use electrically operated air-break power circuit breakers controlled from the DCS. Each power circuit breaker will have a solid-state trip device. If an electric fire pump is required, its feeder will be mechanically operated only. The low voltage switchgear will supply power to the low-voltage MCCs. The low voltage switchgear will be located indoors. The low-voltage switchgear will receive 480V power from the 4.16kV- 0.480kV transformer through non-segregated phase bus duct. A multimeter will be mounted on the front of each low-voltage switchgear to display bus voltage and current, kW, and WAR for the incoming feed to that low-voltage switchgear. Each low voltage switchgear will be designed with an integral high resistance grounding system with a self-contained annunciator and pulsing contactor. Ground fault detection will be provided with an alarm indication to the DCS. All low voltage switchgear will have provisions and to accommodate a future vertical section. 4.13 Low Voltage Motor Control Centers Low voltage motor control centers (MCCs) will be rated 480V nominal, three-phase, three- wire and will supply 480V non-motor loads, motors from 3/4 hp up to and including 200 hp, motor-operated valves, and lighting and distribution panels. Thermal magnetic molded- case circuit breakers will be used for non-motor loads. Each motor starter will consist of a padlockable motor circuit protector; three-phase overload protection; three-pole contactor; hand-off-auto switch; stopped and running indication lights; and control power transformer. Control power transformers will be sized to handle each individual motor space heater Lodi Energy Center 3.4-6 LEC AFC 071608 Rev.A