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OC Motor Pool and Maintenance Shop <br />PDC Project 23017 Enclosed Switches and Circuit Breakers 26 28 16.16 - 4 <br />1.Where electronic circuit breakers equipped with integral ground fault protection are used, <br />provide separate neutral current sensor where applicable. <br />O.Selectivity: Where the requirement for selectivity is indicated,furnish products as required to <br />achieve selective coordination. <br />P.MOLDED CASE CIRCUIT BREAKERS <br />1.Description: Quick-make,quick-break,over center toggle,trip-free,trip-indicating circuit <br />breakers listed and labeled as complying with UL 489,and complying with FS W-C-375 <br />where applicable;ratings,configurations,and features as indicated on the drawings. <br />2.Interrupting Capacity: <br />a.Provide circuit breakers with interrupting capacity as required to provide the short circuit <br />current rating indicated. <br />b.Fully Rated Systems: Provide circuit breakers with interrupting capacity not less than <br />the short circuit current rating indicated.Series rating is not allowed. <br />3.Conductor Terminations: <br />a.Provide mechanical lugs for circuit breaker frame sizes less than 400 amperes. <br />b.Provide compression lugs for circuit breaker frame sizes 400 amperes and above. <br />c.Lug Material: Copper,suitable for terminating copper conductors only. <br />4.Thermal Magnetic Circuit Breakers: For each pole,furnish thermal inverse time tripping <br />element for overload protection and magnetic instantaneous tripping element for short circuit <br />protection. <br />a.Provide field-adjustable magnetic instantaneous trip setting for circuit breaker frame <br />sizes 100 amperes and larger. <br />5.Electronic Trip Circuit Breakers: Furnish solid state,microprocessor-based,true rms sensing <br />trip units. <br />a.Provide the following individually field-adjustable trip response settings: <br />1)Long time pickup,adjustable by setting dial. <br />2)Long time delay. <br />3)Short time pickup and delay. <br />4)Instantaneous pickup. <br />5)Ground fault pickup and delay where ground fault protection is indicated. <br />6.Multi-Pole Circuit Breakers: Furnish with common trip for all poles. <br />PART 3 EXECUTION <br />3.01 EXAMINATION <br />A.Verify that field measurements are as indicated. <br />B.Verify that the ratings of the enclosed switches are consistent with the indicated requirements. <br />C.Verify that mounting surfaces are ready to receive enclosed safety switches. <br />D.Verify that conditions are satisfactory for installation prior to starting work. <br />3.02 INSTALLATION <br />A.Install products in accordance with manufacturer's instructions. <br />B.Install enclosed switches securely,in a neat and workmanlike manner. <br />C.Arrange equipment to provide minimum clearances in accordance with manufacturer's instructions <br />and NFPA 70. <br />D.Provide required support and attachment in accordance with Section 26 05 29. <br />E.Install enclosed switches and breakers plumb. <br />F.Except where indicated to be mounted adjacent to the equipment they supply,mount enclosed <br />switches such that the highest position of the operating handle does not exceed 79 inches above <br />the floor or working platform. <br />G.Provide grounding and bonding in accordance with Section 26 05 26. <br />Docusign Envelope ID: EF9C08D2-5B75-438B-8D6D-8473F81BD7C4