UL 73:2006 pdf download – Motor-Operated Appliances.
40 Temperature Tests
40.1 General
40.1.1 An appliance shall be tested as uescriueu in u.i. I.) — 4u.. arid snau nui reach a temperature at any point high enough to cause a nsk of fire, to damage any materials in the appliance, or to exceed the temperature rises specified in Table 401.
40.1.2 A thermal- or oveiload-protective device shall not open the circuit dunng the temperature test.
40.13 All values of temperature rise in Table 40.1 are based on an assumed ambient temperature of 25 ‘C (77 IF). Tests may be conducted at any ambient temperature within the range of 10 — 40”C (50 — 104F).
40.1.4 For the temperature test. the voltage of a direct-current supply circuit is to be 115 V or 230 V. and that of an alternating-current circuit is to be 120 V or 240 V. depending on whether the appliance has a nominal voltage rating 01115 or 230 V.
40.1.5 An appliance having a single frequency rating is to be tested at that frequency. An appliance rated ac/dc or dc-60 Hz is to be tested on direct current or 60-Hz alternating current, whichever results in higher temperatures. An appliance rated 25 — 60 Hz or 50 — 60 Hz is to be tested on 60-Hz alternating current.
401 6 Ordinarily, coil or winding temperatures are to be measured by thermocouples unless the coil is inaccessible lot mounting of these devices — for example. a coil immersed In sealing compound — or unless the coil wrap includes thermal insulation or more than two layers — 132 in (0.8 mm) maximum — of cotton, paper, rayon, or the like. For a thermocouple-measured temperature of a coil of an alternating-current motor, other than a universal motor, having a diameter of 7 In (178 mm) or less — items 7 and 9 in Table 40.1 — the thermocouple is to be mounted on the integrally applied insulation on the conductor.
40.2 Maximum normal load
40.2.1 General
40.2.1,1 In tests on an appliance, maximum normal load Is considered to be the load that appoxlmates as closely as possible the most severe conditions at normal use. Ills not a deliberate overload except as the conditions of actual use are likely to be somewhat more severe than the maximum load conditions that are recommended by the manufacturer of the appliance. Test loads that have been found to be close approximations of the most severe conditions of normal use are described In 40.2.2.1 — 40.2.3.1 for some common appliances. However, appliances having features not contemplated in these test procedures may be tested as necessary to meet the intent of these requirements.
40.2.2 Carbonators
40.2.2.1 A carbonator is to be operated continuously, until temperatures are constant, with maximum rated carbon dioxide gas pressure — but at not less than 125 psi (861 kPa) pressure — and maximum steady water flow. The pressure and flow may be modified if maximum input occurs at other than maximum rated gas pressure and maximum steady flow,
402.3 Engravers
40.2,3,1 The input test on an engraver is to be conducted while engraving steel. For the temperature test, the engraver is to be operated under no load in cycles of 5 mm on followed by 5 mm off until constant temperatures are attained.
41 Surface Temperature Tests
41.1 Exterior surfaces
41.1.1 A cord-connected appliance of the hand-supported type shall not attain a temperature of more than 1 25C (257F) on any exterior surface that may be laid on combustible material or against which combustible material may be laid, and there shall be no emission of smoke or molten material.
41.1.2 To determine whether an appliance complies with the requirement in 41.1.1, the appliance is to be operated at the voltage and frequency specified in 40.1.4 and 40.1.5 until constant temperatures are attained. The appliance may be stationary during the test, and simulation of actual service conditions need not be attempted.