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ORANGE COUNTY 230513-2 <br /> <br />Emergency Management Warehouse Building Dehumidification Electrical Motors for HVAC Equipment <br /> <br /> <br />Variable speed motors shall be electronic commutation motors (ECM), brushless DC motors with internal circuitry to 1 <br />convert AC power supplied to DC power to operate the motor. Motor shall be speed-controllable via internal circuitry 2 <br />down to 20% of full speed (i.e., 80% turndown) via 0-10 VDC or 4-20 mADC controller output signal from the building 3 <br />direct digital control system. Motor shall be a minimum of 85% efficient at all speeds. 4 <br /> 5 <br />Bearings shall be prelubricated, antifriction ball bearings or sleeve bearings suitable for radial and thrust loading. 6 <br /> 7 <br /> 8 <br />POLYPHASE MOTORS 9 <br /> 10 <br />Polyphase motors, unless indicated otherwise, shall be in accordance with NEMA MG 1, Design B, medium induction 11 <br />open dripproof (ODP) type, 1.15 service factor, Class F insulation, rated as "Premium" efficiency motors by NEMA. 12 <br /> 13 <br />Motor bearings shall be regreasable, shielded, antifriction ball bearings suitable for radial and thrust loadings. 14 <br /> 15 <br />Motor frames shall be cast iron for motors 10 hp and larger; rolled steel for motors smaller than 10 hp. 16 <br /> 17 <br />For motors with reduced-voltage and multispeed controllers, match wiring connection requirements for controller with 18 <br />required motor leads. Provide terminals in motor terminal box, suited to control method. 19 <br /> 20 <br /> 21 <br />PART 3 - EXECUTION 22 <br /> 23 <br /> 24 <br />GENERAL 25 <br /> 26 <br />Install motors on motor mounting systems in accordance with motor manufacturer's instructions, securely anchored to 27 <br />resist torque, drive thrusts, and other external forces inherent in mechanical work. Secure sheaves and other drive 28 <br />units to motor shafts with keys and Allen set screws, except motors of 1/3 HP and less may be secured with Allen set 29 <br />screws on flat surface of shaft. Unless otherwise indicated, set motor shafts parallel with machine shafts. 30 <br /> 31 <br /> 32 <br />OWNER INSTRUCTION AND TRAINING 33 <br /> 34 <br />Provide Owner instruction and training in accordance with Section 019926. 35 <br /> 36 <br /> 37 <br />END OF SECTION 230513 38 <br />DocuSign Envelope ID: 7668B866-6C26-485C-9A45-DAAB5D4BD951