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仔细阅读62368下面条款
* v* R" \0 ]5 S, f& `5.4.1.8 Determination of working voltage! A( r4 C2 h8 F7 F
5.4.1.8.1 General
0 m4 E$ h) p+ {& iIn determining working voltages, all of the following requirements apply:7 q3 T4 L" U% v/ v* a& s- c* H- L
a) unearthed accessible conductive parts are assumed to be earthed;+ N7 G+ }- L$ d2 m* v, l- a
b) if a transformer winding or other part is not connected to a circuit that establishes its- _: W5 r; W& U+ Y1 f' T/ B
potential relative to earth, the winding or other part are assumed to be earthed at a point by
" Y% s" Y0 ?5 p, S' W" Mwhich the highest working voltage is obtained;- J0 @" }# ]) t& r; i
c) except as specified in 5.4.1.6, for insulation between two transformer windings, the highest# ^$ N5 j. y3 R- w8 i& N8 I
voltage between any two points in the two windings is the working voltage, taking into# y2 e- n% R6 Y
account the voltages to which the input windings will be connected;' E+ \! ~8 p# P1 _8 w1 m3 O
d) except as specified in 5.4.1.6, for insulation between a transformer winding and another
Q" A5 z( |2 ^& c/ Spart, the highest voltage between any point on the winding and the other part is the working( G, f) X9 S& p+ a& c& ]
voltage;
; \" h3 g* r& h+ R! M5 J; v" f$ C; G' u4 X2 g K- \
e) where double insulation is used, the working voltage across the basic insulation is
+ Y* z' X6 ?5 a i" |9 O. idetermined by imagining a short-circuit across the supplementary insulation, and vice
z3 [- l& I0 [! I8 U/ V8 {versa. For double insulation between transformer windings, the short-circuit is assumed
. n- q; g8 L6 p5 k j3 n6 w9 `+ {) C: Xto take place at the point by which the highest working voltage is produced across the- c( |) Q! w0 k7 J+ V7 N3 }
other insulation;) t. E a; d& b
f) when the working voltage is determined by measurement, the input voltage supplied to the
+ F" w. l- n4 u) r4 Y7 @, V. iequipment shall be the rated voltage or the voltage within the rated voltage range that
$ r9 W' U! W) g) b* presults in the highest measured value;' Y( M7 T6 i3 U/ L, j9 U3 s" G
g) the working voltage between any point in the circuit supplied by the mains and* O* q8 X3 H2 M( c) h" B/ v
– any part connected to earth; and
+ s0 W; o3 X( U! b– any point in a circuit isolated from the mains,& p, ~* v5 U. S) Q
shall be taken as the greater of the following:
/ ]3 [: e* |* n' i. H– the rated voltage or the upper voltage of the rated voltage range; and
! o$ [* J5 a7 p8 Z0 G3 |4 z– the measured voltage;
' z6 t( p/ h8 Kh) when determining the working voltage for an ES1 or ES2 external circuit, the normal
8 F5 K2 e! n& E; g' Boperating voltages shall be taken into account. If the operating voltages are not known, the1 G# o* P1 t! R+ Y3 m7 d) ^! I9 b; g1 }
working voltage shall be taken as the upper limits of ES1 or ES2 as applicable. Short
7 i0 x J/ h- Uduration signals (such as telephone ringing) shall not be taken into account for determining
% R$ T( ~+ B9 w: x( wworking voltage;: w7 J0 e$ R) ~8 j& g
i) for circuits generating starting pulses (for example, discharge lamps, see 5.4.1.7), the
' N& W% t4 I: v x3 W0 ^1 e# w5 ?working voltage is the peak value of the pulses with the lamp connected but before the
* n) V9 ?* A6 i: Blamp ignites. The frequency of the working voltage to determine the minimum clearance
; x V# M# B- L# d' I# i. Sshall be taken as less than 30 kHz. The working voltage to determine minimum creepage
& ~7 B& p5 h0 }! F6 h% _distances is the voltage measured after the ignition of the lamp. |
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