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H. Vertical Section G <br /> 1. Pump P-103, 300 hp, Solid-state starter cubicle. <br /> I. Vertical Section H <br /> 1. Pump P-102, 300 hp, Solid-state starter cubicle. <br /> J. Vertical Section I (future) <br /> 1. Pump P-101, 150 hp, Variable Frequency Drive. <br /> The opinion of cost for the Motor Control Center is based on an Allen-Bradley line- <br /> up. The 300 hp starters are a solid-state controller. The main function of a solid-state <br /> controller is to provide a soft start or stepless reduced voltage start of the AC motors. The <br /> solid-state controller allows adjustment of the time for the soft start ramp, or current limit <br /> maximum value, which enables selection of the starting characteristic to meet the <br /> application. The major advantages of the solid-state controller are the elimination of a <br /> current transition point and the capability of adjusting the time to reach full voltage. As <br /> a result there is no large current surge when solid-state controllers are set-up and correctly <br /> matched to the application. To maintain a NEMA 12 rating on the MCC the solid-state <br /> starters will have a bypass contractor installed in parallel, when the motor is up to speed, <br /> the bypass contractor is pulled in for run.. The bypass mode reduces the amount of heat <br /> produced by the SCRs in the solid state controller. Note that when the in bypass mode the <br /> protection functions that are inherit with the solid-state controller are disabled, and the <br /> drive would be no different than a normal across-the-line starter. In addition an isolation <br /> contractor will be installed ahead of the solid-state controller, when an isolation contractor <br /> is not used, hazardous voltages are present at the load terminals of the power module even <br /> when the controller is turned off. The isolation contacter is used to provide automatic <br /> electrical isolation of the controller and motor circuit when the controller is shut down. If <br /> the solid-state controllers are not desired for the three 300 hp motors and a full-voltage <br /> non-reversing starter is used instead, there will be a $2,500 deduction from each starter <br /> in the motor control center, additionally the .size of each of the 300 hp MCC vertical <br /> section will reduce by five inches. <br /> 14 <br />