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UL778中的Dielectric voltage-ithstand:4 c7 Z% L, O3 W- X4 V
35.1.1 A pump shall with stand for 1 minute without breakdown the application of a 60-hertz, essentially sinusoidal potential:
% J( x2 J r6 G3 h4 xa)Between live parts and grounded dead metal and
" @! q) C; {, A* X1 f( a/ W! Ob)Between the terminals of a capacitor used for radio interference elimination or arc suppression.The test potential shall be as follows:% {, I3 L: D1 }" F N/ i H
1)One thousand volts for a nonsubmersible pump rated no more than 250 volts, and no more than 1/2 horsepower(373 watt output).
3 H# |# l$ P+ E, `2)One thousand volts plus twice the rated voltage for a nonsubmersible pump rated more than 250 volts, or more than 1/2 horsepower.- }- C7 [* ?' s3 \ H1 A* k
3)One thousand volts plus twice the rated voltage for a submersible pump.- P7 P& \! @0 Q7 X* h7 @' _
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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.
" V+ G! d2 n6 W! J5 p% k2 pException: 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.
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35.1.3 In the case of a DC pump, the test potential is to be direct current.; P# a- o7 n" y/ W1 K
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看的不是很明白,那位高手幫忙指點指點。 |
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