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City of Everett 26 05 73.16 -4 <br /> Inductive Charging Infrastructure for Everett Transit <br /> b. Circuit Breakers: <br /> 1) Adjustable pickups and time delays (long time, short time, and <br /> ground). <br /> 2) Adjustable time-current characteristic. <br /> 3) Adjustable instantaneous pickup. <br /> 4) Recommendations on improved trip systems, if applicable. <br /> c. Fuses: Show current rating, voltage, and class. <br /> E. Time-Current Coordination Curves: Determine settings of overcurrent protective <br /> devices to achieve selective coordination. Graphically illustrate that adequate time <br /> separation exists between devices installed in series, including power utility company's <br /> upstream devices. Prepare separate sets of curves for switching schemes and for <br /> emergency periods where power source is local generation. Show the following <br /> information: <br /> 1. Device tag and title, one-line diagram with legend identifying portion of system <br /> covered. <br /> 2. Terminate device characteristic curves at point reflecting maximum symmetrical <br /> or asymmetrical fault current to which device is exposed. <br /> 3. Identify device associated with each curve by manufacturer type, function, and, if <br /> applicable, tap, time delay, and instantaneous settings recommended. <br /> 4. Plot the following listed characteristic curves, as applicable: <br /> a. Power utility's overcurrent protective device. <br /> b. Medium-voltage equipment overcurrent relays. <br /> c. Medium- and low-voltage fuses including manufacturer's minimum melt, <br /> total clearing, tolerance, and damage bands. <br /> d. Low-voltage equipment circuit-breaker trip devices, including <br /> manufacturer's tolerance bands. <br /> e. Transformer full-load current, magnetizing inrush current, and ANSI <br /> through-fault protection curves. <br /> f. Cables and conductors damage curves. <br /> g. Ground-fault protective devices. <br /> h. Motor-starting characteristics and motor damage points. <br /> i. Generator short-circuit decrement curve and generator damage point. <br /> j. Largest feeder circuit breaker in each motor-control center and panelboard. <br /> 5. Maintain selectivity for tripping currents caused by overloads. <br /> 6. Maintain maximum achievable selectivity for tripping currents caused by <br /> overloads on series-rated devices. <br /> 7. Provide adequate time margins between device characteristics such that <br /> selective operation is achieved. <br /> 8. Comments and recommendations for system improvements. <br /> 26 05 73.16 -4 COORDINATION STUDIES <br />