标题: UL778 [打印本页] 作者: JIES 时间: 2008-10-17 14:18 标题: UL778 UL778中的Dielectric voltage-ithstand： 6 U# {2 @8 n2 ^$ {35.1.1 A pump shall with stand for 1 minute without breakdown the application of a 60-hertz, essentially sinusoidal potential:3 Q' [. Z1 l" M
a)Between live parts and grounded dead metal and x+ K5 b) H2 ~8 E# Gb)Between the terminals of a capacitor used for radio interference elimination or arc suppression.The test potential shall be as follows: 7 E8 g$ G( p `# d. c1)One thousand volts for a nonsubmersible pump rated no more than 250 volts, and no more than 1/2 horsepower(373 watt output). ) c* \. `5 B( I" _8 C1 R3 F) ]2)One thousand volts plus twice the rated voltage for a nonsubmersible pump rated more than 250 volts, or more than 1/2 horsepower.2 I* f# ?! H; I9 Q
3)One thousand volts plus twice the rated voltage for a submersible pump.: q, L" x' p; b& w
. q9 d& R( t$ F35.1.2 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. ' U& i1 ~: B: A5 q2 e% a" Z, WException: 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.5 v$ R5 G9 k$ I! H
( N* O: c6 y) L1 |35.1.3 In the case of a DC pump, the test potential is to be direct current. 1 a6 n+ R: H, U4 {: m8 X& J8 p Q9 ]0 K* L8 R; R看的不是很明白，那位高手幫忙指點指點。