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UL778中的Dielectric voltage-ithstand:
! u, p: t* D" v. `9 X" ?35.1.1 A pump shall with stand for 1 minute without breakdown the application of a 60-hertz, essentially sinusoidal potential:) q I; A2 o4 t% z4 q
a)Between live parts and grounded dead metal and- p6 L# w3 F0 f6 j) E% `
b)Between the terminals of a capacitor used for radio interference elimination or arc suppression.The test potential shall be as follows:
" J: Z$ `& g r1)One thousand volts for a nonsubmersible pump rated no more than 250 volts, and no more than 1/2 horsepower(373 watt output).
( C% R, C9 t# `2)One thousand volts plus twice the rated voltage for a nonsubmersible pump rated more than 250 volts, or more than 1/2 horsepower.
& P" S& N6 i$ g9 w1 |& a% e+ F3)One thousand volts plus twice the rated voltage for a submersible pump.. j: W7 z+ v. {( Z$ s$ L: f1 T
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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.9 f: @0 ] n! Q/ Z# I% D
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.. ?% {( H. f: d: k3 o/ X5 w
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35.1.3 In the case of a DC pump, the test potential is to be direct current.. L- ~- p3 z G9 }8 V6 o9 s+ f2 R4 r
- d1 F" p1 n, f6 x看的不是很明白,那位高手幫忙指點指點。 |
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