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仔细阅读62368下面条款
1 V4 A Y9 Y: Y3 k" M1 `! {5.4.1.8 Determination of working voltage
Y$ v% [$ ^) x+ g2 r0 w t9 Q5.4.1.8.1 General1 k; p0 q. [/ @9 a2 W6 w
In determining working voltages, all of the following requirements apply:. N ~1 t% @0 a, Y
a) unearthed accessible conductive parts are assumed to be earthed;
! L4 `0 Q- a7 Fb) if a transformer winding or other part is not connected to a circuit that establishes its, a" K: @6 u" \0 q& \0 R9 u: K0 H2 m1 Q
potential relative to earth, the winding or other part are assumed to be earthed at a point by" C- O4 y; H9 F7 C: A' g: {# r
which the highest working voltage is obtained;, t# M6 J( H5 p; I0 n" w$ N
c) except as specified in 5.4.1.6, for insulation between two transformer windings, the highest6 v" |5 B$ \* x0 \" i" H O
voltage between any two points in the two windings is the working voltage, taking into! t8 _9 j4 e* F* F$ O6 K
account the voltages to which the input windings will be connected;& r* C" d* d* ?, G# R& E* _
d) except as specified in 5.4.1.6, for insulation between a transformer winding and another$ m/ z* _/ N: H/ j% H* N
part, the highest voltage between any point on the winding and the other part is the working/ J$ N0 N1 E& {6 U- x/ y
voltage;; Q( Z% }( y n+ s6 Y1 S# ~
$ y" ^% y. c! f+ [. b' y% `2 T/ t
e) where double insulation is used, the working voltage across the basic insulation is0 ?' {" T4 X- B6 U) I7 a/ H
determined by imagining a short-circuit across the supplementary insulation, and vice% }8 z* A$ n- U) S3 D
versa. For double insulation between transformer windings, the short-circuit is assumed
' d5 |$ t( h/ P' i" Q" B. Ato take place at the point by which the highest working voltage is produced across the m# n0 V; V3 K; H1 _8 k
other insulation;/ m' W' V& Z& e6 w
f) when the working voltage is determined by measurement, the input voltage supplied to the
! _- S) n, h( y) n; T% sequipment shall be the rated voltage or the voltage within the rated voltage range that* P: f. v8 ]# }: T; x
results in the highest measured value;
% [. X% K3 w2 d4 F- T. k4 Jg) the working voltage between any point in the circuit supplied by the mains and
# y" n5 R" Q' b% R; ]– any part connected to earth; and. Y' d: h: A5 D8 a
– any point in a circuit isolated from the mains,
- T' O2 p; k8 k1 Tshall be taken as the greater of the following:
L/ o+ X5 q3 H( o* o– the rated voltage or the upper voltage of the rated voltage range; and$ V; W# u/ {9 E% [! x
– the measured voltage;
8 q/ ^& q+ }% A, a# C; Ch) when determining the working voltage for an ES1 or ES2 external circuit, the normal9 }3 Z9 m0 }5 k
operating voltages shall be taken into account. If the operating voltages are not known, the7 k; F3 m+ A2 z: y$ j h
working voltage shall be taken as the upper limits of ES1 or ES2 as applicable. Short
/ g4 b: q2 T! f4 Z, Wduration signals (such as telephone ringing) shall not be taken into account for determining' D+ H% t5 {4 B- n5 U% P0 O: O) ]5 s" |2 y
working voltage;" k. z# t3 ~4 a* ?- I, P( K* a% q
i) for circuits generating starting pulses (for example, discharge lamps, see 5.4.1.7), the7 m4 I3 Q U: U7 \0 T; Z% {
working voltage is the peak value of the pulses with the lamp connected but before the# x8 s/ H; D, i% y' N( L- `
lamp ignites. The frequency of the working voltage to determine the minimum clearance
1 F7 d8 ]4 u! d* q7 l/ X Kshall be taken as less than 30 kHz. The working voltage to determine minimum creepage
6 N# k8 V. X9 m0 bdistances is the voltage measured after the ignition of the lamp. |
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