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DocuSign Envelope ID: 9826C043- 4C32- 49CD- A4CC- DC28ABAB7CE7 <br />SECTION 237530 - COMMON MOTOR REQUIREMENTS FOR HVAC EQUIPMENT <br />H. Insulation: Class F. <br />Code Letter Designation: <br />1. Motors 15 HP and Larger: NEMA starting Code F or Code G. <br />2. Motors Smaller than 15 HP: Manufacturer's standard starting characteristic. <br />Enclosure Material: Cast iron for motor frame sizes 324T and larger; rolled steel for motor frame <br />sizes smaller than 324T. <br />2.4 POLYPHASE MOTORS WITH ADDITIONAL REQUIREMENTS <br />A. Motors Used with Reduced - Voltage and Multispeed Controllers: Match wiring connection <br />requirements for controller with required motor leads. Provide terminals in motor terminal box, suited <br />to control method. <br />B. Motors Used with Variable Frequency Controllers: Ratings, characteristics, and features coordinated <br />with and approved by controller manufacturer. <br />1. Windings: Copper magnet wire with moisture - resistant insulation varnish, designed and <br />tested to resist transient spikes, high frequencies, and short time rise pulses produced by <br />pulse -width modulated inverters. <br />2. Energy- and Premium - Efficient Motors: Class B temperature rise; Class F insulation. <br />3. Inverter -Duty Motors: Class F temperature rise; Class H insulation. <br />4. Thermal Protection: Comply with NEMA MG 1 requirements for thermally protected motors. <br />2.5 SINGLE -PHASE MOTORS <br />A. Motors larger than 1/20 hp shall be one of the following, to suit starting torque and requirements of <br />specific motor application: <br />1. Permanent -split capacitor. <br />2. Split phase. <br />3. Capacitor start, inductor run. <br />4. Capacitor start, capacitor run. <br />B. Multispeed Motors: Variable- torque, permanent - split- capacitor type. <br />C. Bearings: Prelubricated, antifriction ball bearings or sleeve bearings suitable for radial and thrust <br />loading. <br />D. Motors 1/20 HP and Smaller: Shaded -pole type. <br />E. Thermal Protection: Internal protection to automatically open power supply circuit to motor when <br />winding temperature exceeds a safe value calibrated to temperature rating of motor insulation. <br />Thermal - protection device shall automatically reset when motor temperature returns to normal range. <br />PART 3 - EXECUTION (Not Applicable) <br />END OF SECTION 237530 <br />Reece, Noland & McElrath, Inc. 237530-2 NOrange County Board of Elections <br />Orange Co., NC 05/04/18 <br />