UL 1004-3:2012 free download Thermally Protected Motors
29.1.2 It shall not be necessary to repeat the Locked Rotor Endurance Test, Section 41B, for alternateminor insulation system components.
Added 29.1.2 effective September 15,2014
29.2 The performance tests are to be conducted on representative samples of motor/protectorcombinations.The number of samples required to be tested are to be consistent with the range of motorsto be protected.
29.2 effective September 15,2014
29.3 A protector calibrated to have a tolerance in excess of +5℃(±9F) of the nominal openingtemperature or±15℃(+27F) of the closing temperature, shall be tested in accordance with 29.4 todetermine that the wider tolerance protector has an intended locked-rotor cycling life.
29.3 effective September 15, 2014
29.4 As required by 29.3, the following motor/protector combinations are to be tested to all temperatureand endurance requirements as follows:
a)One sample protector calibrated to open at the maximum temperature shall be subjected toall tests required in this Standard; and
b)One sample calibrated to open at the minimum temperature and close at the maximumtemperature shall be subjected to the Locked Rotor Endurance Test, Section 41B, except theduration is to be 18 days.
29.4 effective September 15,2014
29.5 When a secondary or back-up protector is provided, it shall not operate under any conditions of test.
29.5 effective September 15,2014
29.6 Polyphase motors shall be provided with protectors so that each phase winding is protected fromoverheating.
29.6 effective September 15,2014
29.7 A single-operation device shall not reset itself at a temperature higher than minus 35 ℃(minus31 F).
29.7 effective September 15,2014
29.8 During the tests, the current is to be monitored and recorded at key events such as when the loadis increased during the Running Heating Temperature Test,Section 41C, or when the protector tripsduring the Locked Rotor Temperature Test,Section 41A.
Exception: The current is not required to be monitored during the Locked Rotor Endurance Test, Section41B.
29.8 effective September 15,2014
29.9 The primary protector shall operate during the Locked Rotor Temperature Test, Section 41A, andduring the Locked Rotor Endurance Test, Section 41B.
29.9 effective September 15,2014
29.10 The primary protector shall not operate during the Ratings Tests,Section 30 of UL 1004-1,orduring the Temperature Test,Section 31 of UL 1004-1.
29.10 effective September 15,2014
29.11 Manufacturers that choose to provide a thermal motor protector in their impedance protected motormay, at their option, elect to have the motor evaluated to the requirements of this Standard as a thermallyprotected motor. If so, at the manufacturer’s option, the motor will be either tested at an elevated ambientor be tested at an elevated voltage in either case sufficient to cause the thermal protector to operate underlocked rotor conditions and thus the motor to behave as a thermally protected motor.
29.11 effective September 15,2014
UL 1004-3:2012 free download
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