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仔细阅读62368下面条款; j5 a6 I/ I( a R E
5.4.1.8 Determination of working voltage$ R! ?, X+ F, M( F8 i
5.4.1.8.1 General
! A; w0 u) I I8 `) m! [8 xIn determining working voltages, all of the following requirements apply:
1 w5 v; v. L. I8 \3 f2 v- `% \+ ka) unearthed accessible conductive parts are assumed to be earthed;2 x9 v& N: h1 ^
b) if a transformer winding or other part is not connected to a circuit that establishes its. M. ]& f8 w3 i1 S' {8 g2 R" A
potential relative to earth, the winding or other part are assumed to be earthed at a point by
7 n! s/ I% G) I7 O1 Wwhich the highest working voltage is obtained;
3 F/ q* V1 J' S/ ]' lc) except as specified in 5.4.1.6, for insulation between two transformer windings, the highest" `/ J9 }% q/ G4 v4 o( U
voltage between any two points in the two windings is the working voltage, taking into6 Q2 q# [% J9 ]9 w
account the voltages to which the input windings will be connected;
7 I0 `) d6 F! K0 n3 D0 Td) except as specified in 5.4.1.6, for insulation between a transformer winding and another7 I* i$ Q4 V4 r6 }
part, the highest voltage between any point on the winding and the other part is the working& w& k6 I6 b! a9 N+ w
voltage;
0 A& a: n6 A0 X g: ]- A. |- Z( L' t; m7 C7 Y+ d
e) where double insulation is used, the working voltage across the basic insulation is9 O7 C$ ^7 p4 Y- e# z7 E# }" g
determined by imagining a short-circuit across the supplementary insulation, and vice
8 H& s3 f/ V5 oversa. For double insulation between transformer windings, the short-circuit is assumed
a, X+ b8 \( h3 X+ q. Z! wto take place at the point by which the highest working voltage is produced across the& G4 q/ U4 U( {4 b
other insulation;
8 G5 R) ^% B9 A4 {$ ~f) when the working voltage is determined by measurement, the input voltage supplied to the" V, I/ z' }+ I: J" t- J
equipment shall be the rated voltage or the voltage within the rated voltage range that- ^$ i7 R4 \/ d) `$ @# P
results in the highest measured value;, l7 n5 l+ U$ B0 ?. p2 k# ]
g) the working voltage between any point in the circuit supplied by the mains and
9 \$ R9 l: S7 C0 X% H0 S- @– any part connected to earth; and5 d, W6 g9 v$ N) M; V" d0 n: x! O
– any point in a circuit isolated from the mains,
( w7 m8 w8 U" T9 Q' |- vshall be taken as the greater of the following:
. Z& \0 Z0 ]+ O) ~, r– the rated voltage or the upper voltage of the rated voltage range; and
7 S; ]9 o5 \* v7 v! [– the measured voltage;
4 @, W* Y: S+ {, M- p& xh) when determining the working voltage for an ES1 or ES2 external circuit, the normal- \# ?' I$ C3 B" l0 K
operating voltages shall be taken into account. If the operating voltages are not known, the3 K4 m1 _4 e5 x5 \# q, ~5 b
working voltage shall be taken as the upper limits of ES1 or ES2 as applicable. Short
7 @" n3 Y8 l5 d# wduration signals (such as telephone ringing) shall not be taken into account for determining
% U0 J. B0 w ^: E7 jworking voltage;9 |" g' ~0 N1 J0 r# \1 w
i) for circuits generating starting pulses (for example, discharge lamps, see 5.4.1.7), the9 b' g0 @. ?, U- u- E
working voltage is the peak value of the pulses with the lamp connected but before the( _- Q7 F: X- m$ _
lamp ignites. The frequency of the working voltage to determine the minimum clearance# c" g5 B# K. F3 ^% A
shall be taken as less than 30 kHz. The working voltage to determine minimum creepage
) y2 q Y4 M0 \3 |: |7 Kdistances is the voltage measured after the ignition of the lamp. |
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