UL 1340-2012 pdf download

UL 1340-2012 pdf download.Hoists.
31.5 A short length of rubber- or thermoplastic-insulated flexible cord may be exposed to a temperature of more than 60°C (140°F), such as at the terminals. However, the individual cord conductors shall be provided with supplementary heat-resistant insulation with the proper dielectric withstand characteristic. See the Dielectric Voltage-Withstand Test. Section 34.
31.6 All values for temperatures in Table 31.1 are based on an assumed ambient temperature of 25°C (77°F). Tests may be conducted at any ambient temperature within the range of 10—40°C (50— 104°F).
31.7 Temperatures are to be measured with thermocouples consisting of wires not larger than 24 AWG (0.21 mm2) and not smaller than 30 AWG (0.05 mm2). When thermocouples are used to determine temperatures in electrical equipment, it is common practice to employ thermocouples consisting of 30 AWG iron and constantan wire and a potentiometer-type instrument; such equipment is to be used whenever referee temperature measurements by thermocouples are necessary. The thermocouple wire is to be in accordance with the requirements specified In the Initial Calibration Tolerances for Thermocouples table in Temperature Measurement Thermocouples, ANSIJISA MC96, 1.
31.8 If the hoist has a single frequency rating. the test is to be conducted at that frequency. F a hoist rated either for alternating current’direct current or direct current. 60 hertz is to be tested on direct current or 60 hertz alternating current, whichever results in higher temperatures. A product rated 25 — 60 hertz or 50 — 60 hertz is to be tested on 60-hertz alternating current.
31.9 It the hoist incorporates a reel for the power-supply cord, one-third of the length of the cord is to be unreeled for the test.
31.10 Tests are to be conducted under actual operating conditions.
32 StraIn-Relief Test
32.1 The strain•relief means of a power-supply cord shall not permit the cord to move in a way that indicates stress would have been transmitted to the cord connections when a 35-pound (1 5.9-kg) weight is suspended from the hoist by the cord for 1 minute and the strain-relief means is stressed from any angle permitted by the construction of the ho4st.
32.2 A power-supply cord shall withstand for 1 minute. 50 ounce-inches (0.35 N’m) of torque applied I inch (25.4 mm) from the strain reliet means without damage to the cord and without transmitting the torque to the terminations.
33.4 The hoist is to be examined to determine that all electrical parts, including motor windings, are not wetted and that there Is no water within the enclosures of electrical parts prior to rain exposure.
33.5 The hoist is to be positioned in the focal area of the three spray heads so that the greatest quantity of water will enter the hoist.
33.6 The hoist is to be operated so that electrical components are energized. The hoist is to be tested under intended conditions considered most likely to cause waler to enter electrical enclosures o contact electrical components. It may be necessary to operate the hoist under various modes or to de-energize the hoist if more adverse conditions could result. Each exposure is to be for 1 hour.
33.7 The insulation resistance is to be measured 1 minute after application of the voltage obtained by using the series-voltmeter method or the equivalent, and a direct•current circuit. After measurement of the insulation resistance, the entire hoist Is to be subjected to the Leakage-Current Test. SectIon 26, and the Dielectric Voltage-Withstand Test, Section 34.
33.8 The hoist is to be dried prior to the second or subsequent exposures unless without such preparation, the insulation resistance between live parts and dead metal parts is greater than 50.000 ohms.
34 DIelectric Voltage-Withstand Test
341 An essentially sinusoidal 60-hertz potential of 1000 volts plus twice the rated voltage is to be applied between live parts and dead metal parts of the hoist for 1 minute. The temperature of the hoist Is to be the same as the value recorded during the Temperature Test. Section 31. There shall not be dielectric breakdown.
Exception: If a hoist empioys an induction motor rated less than 1,2 horsepower (373 W output) and 250 volts or less, the test potential for the motor, but not for the remainder of the holst, is to be 1000 volts.
34.2 When applying the Exception to 34.1 to a motor not rated in horsepower, the appropriate table of the National Electrical Code. NFPA 70, is to be used which gives the reLationships between horsepower and full-load currents for motors. For a universal motor, the table applying to a single-phase, alternating-current motor is to be used if the motor is marked for use on alternating current only; otherwise, the table applying to direct-current motors is to be used.