UL-1030:2015 pdf free download – STANDARD FOR SAFETY Sheathed Heating Elements.
a) The meter is to have an input impedance of 1500 ohms resistive shunted by a capacitance of 0.15 microfarad;
b) The meter is to indicate 1.11 times the average of the full-wave rectified composite waveform of voltage across the resistor or current through the resistor; and
c) Over a frequency range of 0 — 100 kilohertz, the measurement circuitry is to have a frequency response — ratio of indicated to actual value of current — that is equal to the ratio of the impedance of a 1500 ohm resistor shunted by a 0.15 microfarad capacitor to 1500 ohms. At an indication of 0.5 milliampere, the measurement is to have an error of not more than 5 percent at 60 hertz.
12.3 The meter is to be connected between the sheath and the grounded supply conductor.
12.4 A sample of the heating element is to be tested for leakage current when connected to a supply voltage of 120 or 240 volts, as applicable. The test sequence, with reference to the measuring circuit — Figure 12.1 — is to be as follows:
a) With switch Si open, the element is to be connected to the measuring circuit. Leakage current is to be measured using both positions of switch S2;
b) Switch Si is then to be closed energizing the element, and within five seconds, the leakage current is to be measured using both positions of switch S2; and
14.3 Sheath temperatures are to be measured by thermocouples attached to the hottest points on the sheath by welding, brazing, or other equivalent means.
14.4 Immediately after the temperature test and with the element at room temperature:
a) A heating element requiring testing in accordance with Section 12, Leakage Current Test, shall be subjected to a repeat leakage current test. The leakage current shall not be more than the applicable value specified in Table 12.1;
b) A heating element not requiring testing in accordance with Section 12 shall have an insulation resistance not less than 50,000 ohms; and
c) A heating element shall comply with the dielectric voltage-withstand test in 10.1.1.
MANUFACTURING AND PRODUCTION TESTS
15 Dielectric Voltage-Withstand Test
15.1 Each heating element shall withstand without electrical breakdown, as a routine production-line test, the application of a potential as specified in Table 15.1 applied between live and exposed dead metal parts.
15.2 The production-line test shall be in accordance with either the 60-second test or the one-second test in Table 15.1.
15.5 For the one-second single-phase and direct-current tests, the element need not be preheated. The potential is to be applied while the heating element is cold and de-energized.
15.6 For the one-second quadrature test, the test potential is to be applied by the method illustrated in Figure 10.1. The element need not be preheated. The test potential is to be applied while the element is energized.
15.7 The test equipment is to include a visible indication of application of the test potential and an indication of breakdown that is audible or visible or both. In the event of breakdown, manual resetting of an external switch is to be required, or an automatic reject of the unit under test is to result. Other arrangements may be considered and accepted when found to achieve the results contemplated. A 500-volt-ampere or larger capacity transformer need not be used in tests by the manufacturer when the transformer is provided with a voltmeter to measure directly the applied output potential.