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City of Everett 26 05 73.13 - 3 <br /> Inductive Charging Infrastructure for Everett Transit <br /> B. Study descriptions, purpose, basis, and scope. Include case descriptions, definition of <br /> terms, and guide for interpretation of results. <br /> C. One-line diagram of modeled power system, showing the following: <br /> 1. Protective device designations and ampere ratings. <br /> 2. Conductor types, sizes, and lengths. <br /> 3. Transformer kVA and voltage ratings. <br /> 4. Motor and generator designations and kVA ratings. <br /> 5. Switchgear, switchboard, motor-control center, and panelboard designations and <br /> ratings. <br /> 6. Derating factors and environmental conditions. <br /> 7. Any revisions to electrical equipment required by study. <br /> D. Comments and recommendations for system improvements or revisions in written <br /> document, separate from one-line diagram. <br /> E. Protective Device Evaluation: <br /> 1. Evaluate equipment and protective devices and compare to available short-circuit <br /> currents. Verify that equipment withstand ratings exceed available short-circuit <br /> current at equipment installation locations. <br /> 2. Tabulations of circuit breaker, fuse, and other protective device ratings versus <br /> calculated short-circuit duties. <br /> 3. For 600 V overcurrent protective devices, ensure that interrupting ratings are <br /> equal to or higher than calculated 1/2-cycle symmetrical fault current. <br /> 4. For devices and equipment rated for asymmetrical fault current, apply <br /> multiplication factors listed in standards to 1/2-cycle symmetrical fault current. <br /> 5. Verify adequacy of phase conductors at maximum three-phase bolted fault <br /> currents; verify adequacy of equipment grounding conductors and grounding <br /> electrode conductors at maximum ground-fault currents. Ensure that short-circuit <br /> withstand ratings are equal to or higher than calculated 1/2-cycle symmetrical <br /> fault current. <br /> F. Short-Circuit Study Input Data: <br /> 1. One-line diagram of system being studied. <br /> 2. Power sources available. <br /> 3. Manufacturer, model, and interrupting rating of protective devices. <br /> 4. Conductors. <br /> 5. Transformer data. <br /> G. Short-Circuit Study Output Reports: <br /> 1. Low-Voltage Fault Report: Three-phase and unbalanced fault calculations, <br /> showing the following for each overcurrent device location: <br /> a. Voltage. <br /> b. Calculated fault-current magnitude and angle. <br /> c. Fault-point X/R ratio. <br /> d. Equivalent impedance. <br /> 2. Momentary Duty Report: Three-phase and unbalanced fault calculations, <br /> showing the following for each overcurrent device location: <br /> 26 05 73.13 - 3 SHORT-CIRCUIT STUDIES <br />