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仔细阅读62368下面条款
4 p$ Y: h* P z8 V5.4.1.8 Determination of working voltage" m, {9 {6 ?3 B
5.4.1.8.1 General
, G1 T! j, L2 z6 h: H6 y6 e2 _In determining working voltages, all of the following requirements apply:
0 k/ T( T2 z K3 ea) unearthed accessible conductive parts are assumed to be earthed;' I( C% B, A( o/ Y2 U) a, U
b) if a transformer winding or other part is not connected to a circuit that establishes its* _% n$ R% e" [9 ^ j
potential relative to earth, the winding or other part are assumed to be earthed at a point by; e1 w: q9 w! M8 [5 `
which the highest working voltage is obtained;: K$ [0 H$ ^, o
c) except as specified in 5.4.1.6, for insulation between two transformer windings, the highest
2 W F" H; |% i. s* [0 E( U- }voltage between any two points in the two windings is the working voltage, taking into6 v& c- C! F( N- E2 h7 } o
account the voltages to which the input windings will be connected;4 X( E, W& | l* m# ^
d) except as specified in 5.4.1.6, for insulation between a transformer winding and another
4 \; G1 L! n" G$ f# D- w. I: F8 Rpart, the highest voltage between any point on the winding and the other part is the working
% d* Z+ K5 B; R4 B# ~3 k) Hvoltage;
5 k; K S% q4 V4 V3 f+ w7 w: s4 e O8 R2 v/ F* p- q+ |2 J: i* Y( V& N
e) where double insulation is used, the working voltage across the basic insulation is
0 j9 M) O5 H' J! L2 C$ s$ v* @) bdetermined by imagining a short-circuit across the supplementary insulation, and vice5 o* H9 j/ i* g2 E' ^) m
versa. For double insulation between transformer windings, the short-circuit is assumed
/ W8 D$ f3 M" P |6 e3 Hto take place at the point by which the highest working voltage is produced across the- P7 \$ I$ p% ?1 |% m: K
other insulation;, s( W. E# K# l9 s, b/ j
f) when the working voltage is determined by measurement, the input voltage supplied to the
9 S( b+ ?4 p) W8 s& O6 d% Mequipment shall be the rated voltage or the voltage within the rated voltage range that' `( Q! T1 l6 V. y2 P* X
results in the highest measured value;8 |1 `$ B9 R2 K( m3 O" r' X$ l
g) the working voltage between any point in the circuit supplied by the mains and6 @9 k0 `% X% O4 z
– any part connected to earth; and" F* @- ~+ o* L+ T* a; H/ P6 Y; S3 A
– any point in a circuit isolated from the mains,
" E: [/ N4 ]2 D o) W* Nshall be taken as the greater of the following:
# C) P- \; z: W4 b- J2 g% ?2 o– the rated voltage or the upper voltage of the rated voltage range; and M6 \* d/ a3 [1 y; }* _
– the measured voltage;
8 H4 h- A- _" t# y# F, L Xh) when determining the working voltage for an ES1 or ES2 external circuit, the normal
5 T2 S: l" X. h2 n& qoperating voltages shall be taken into account. If the operating voltages are not known, the# _% a" V9 d& N3 c& e: C
working voltage shall be taken as the upper limits of ES1 or ES2 as applicable. Short& _8 h8 A s8 e# _
duration signals (such as telephone ringing) shall not be taken into account for determining
" I( X% j* ~: S' C0 B$ D6 ]. sworking voltage;
4 T7 {2 s) t: U: k+ p6 q# o, ri) for circuits generating starting pulses (for example, discharge lamps, see 5.4.1.7), the. K/ w k' X- D$ l
working voltage is the peak value of the pulses with the lamp connected but before the
; z' r# v ?# l. @lamp ignites. The frequency of the working voltage to determine the minimum clearance
[2 j; X9 h& }7 {& Bshall be taken as less than 30 kHz. The working voltage to determine minimum creepage& e+ G" p$ y/ l: m% k' P r" ]4 X
distances is the voltage measured after the ignition of the lamp. |
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