UL778
UL778中的Dielectric voltage-ithstand:35.1.1 A pump shall with stand for 1 minute without breakdown the application of a 60-hertz, essentially sinusoidal potential:
a)Between live parts and grounded dead metal and
b)Between the terminals of a capacitor used for radio interference elimination or arc suppression.The test potential shall be as follows:
1)One thousand volts for a nonsubmersible pump rated no more than 250 volts, and no more than 1/2 horsepower(373 watt output).
2)One thousand volts plus twice the rated voltage for a nonsubmersible pump rated more than 250 volts, or more than 1/2 horsepower.
3)One thousand volts plus twice the rated voltage for a submersible pump.
35.1.2 The required test potential may be obtained from any convenient source of sufficient capacity at least 500 volt-amperes capable of maintaining the potential at the required test value except during breakdown.The voltage of the source is to be continuously variable.
Exception: A 500 volt-ampere or larger capacity transformer need not be used if the transformer is provided with a voltmeter to directly measure the applied output potential.
35.1.3 In the case of a DC pump, the test potential is to be direct current.
看的不是很明白,那位高手幫忙指點指點。
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