2008-276 D - Laserfiche WebLink

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B . The nominal motor horsepower shall be adequate for the driven machine without infringement upon the motor service factor. Motors driving pumps shall not be overloaded at any head or discharge condition of the pump . C . The motor horsepower shall not be less than the estimated minimum specified for each driven machine . If the estimated minimum horsepower specified is not adequate to satisfy the foregoing restriction or any other requirements of these Specifications , the motor with the next larger horsepower shall be supplied at no additional cost to the Owner . In addition , any changes caused by increase in motor horsepower shall be made by the Contractor at no additional cost to the Owner , such changes may involve circuit breakers , magnetic starters , motor feeder conductors and conduit sizes , etc . D . Motors which are for valve operators, submersible pumps , or motors which are an integral part of Standard Manufactured Equipment, i . e . , non-NEMA mounting, common shaft with driven element, part of domestic or commercial use apparatus may be excepted from these Specifications to the extent that such variation reflects a necessary condition of motor service or a requirement of the specified driven equipment . 2.02 CONSTRUCTION A. All electric motors shall comply with ANSI/NEMA MG 1 . B . Electric motors shall be NEMA Design B , (except as noted in equipment Specifications for motors controlled for variable speed operation and other special motors,) constant speed squirrel-cage induction motors having normal starting torque with low starting current. In no case shall starting torque or breakdown torque be less than the value specified in said ANSI/NEMA MG 1 . Motors shall be suitable for starting as indicated on the Drawings. Refer to Drawings for type of starting requirements . C . Motors shall be rated in accordance with the following, unless otherwise specified: 1 . Motors below '/z h.p . shall be rated 115 volts, single phase , 60 Hertz. Dual voltage motors rated 115 /230 volts, 115 /208 volts , or 120-240 volts are acceptable. 2. Motors %s h.p. and larger shall be rated 230/460 volts, three-phase, 60 hertz, as required and as shown. Dual voltage motors rated 208/230/460 volts are acceptable. D. Unless otherwise specified, service factor shall be a minimum of 1 . 15 . E. Motor speed shall be as specified with the equipment. F . All motors for driven equipment shall be heavy duty unless otherwise specified. Heavy duty motors shall be furnished with Class F tropicalized insulation system and shall be limited to Class B temperature rise, unless otherwise listed in these Specifications. The motor shall be rated to operate at a maximum ambient temperature of 40 degrees C and at the altitudes where the motors will be installed and operated, without exceeding temperature rise limits stated in ANSI/NEMA MG 1 - 12 .42. 044572017 16490 - 4