标题: 求助：工作电压共地问题 [打印本页] 作者: keven2012 时间: 2023-11-6 16:51 标题: 求助：工作电压共地问题 本帖最后由 keven2012 于 2023-11-6 16:52 编辑 8 U B3 Z) R1 ]; |/ A! e3 \
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工作电压测量的共地问题，次级地共N的依据来源于哪里了？ 8 y. C# `" s% x: W- P; B" L* r & _$ s' o% N; _" k1 T1 s作者: zhupinchao 时间: 2023-11-14 20:24
欢迎咨询，相互交流学习 $ u0 _ [% Y" A; S& \作者: 浪漫罗丹 时间: 2024-1-25 17:43
仔细阅读62368下面条款 2 s1 r$ J+ Y' @, R. |8 Z1 T5.4.1.8 Determination of working voltage" g5 T6 T0 f2 r) \+ [& d3 s# B
5.4.1.8.1 General % ?( _( K7 ]. W+ s/ W5 V) O# CIn determining working voltages, all of the following requirements apply: 3 A9 }9 q9 ?4 K& aa) unearthed accessible conductive parts are assumed to be earthed;( Y4 c+ t7 I9 o! p+ U5 V' t
b) if a transformer winding or other part is not connected to a circuit that establishes its# v) o7 n2 M$ f7 u' I+ M
potential relative to earth, the winding or other part are assumed to be earthed at a point by # T' d0 L* j+ j. F$ m9 Wwhich the highest working voltage is obtained;. A+ {9 _# N9 G% p% h0 E
c) except as specified in 5.4.1.6, for insulation between two transformer windings, the highest - Q/ I3 F5 T1 X4 Q) H* I& w# yvoltage between any two points in the two windings is the working voltage, taking into , t' E8 s8 G7 R: g5 B7 Z p% E$ Yaccount the voltages to which the input windings will be connected;1 o' R/ `' `" T1 R4 A7 V! Y& p* b
d) except as specified in 5.4.1.6, for insulation between a transformer winding and another2 ]3 z2 e6 B8 |8 u9 Q* C- ^ {
part, the highest voltage between any point on the winding and the other part is the working : T! c$ q% [0 r( _$ a1 ^- @voltage;5 z& X. @- l% l6 o
) c9 Q' H, x0 m( d5 c
e) where double insulation is used, the working voltage across the basic insulation is& y) \" b |" H. C
determined by imagining a short-circuit across the supplementary insulation, and vice / o: H1 {2 v( Oversa. For double insulation between transformer windings, the short-circuit is assumed6 p) a o; D/ O9 V( c! G
to take place at the point by which the highest working voltage is produced across the & h2 h; F" U @2 B- Q6 @other insulation;6 ?/ z. k. ]# k9 n& g' [
f) when the working voltage is determined by measurement, the input voltage supplied to the/ k9 n+ E6 E' V4 S+ J# Z
equipment shall be the rated voltage or the voltage within the rated voltage range that ?; W& t0 T, K1 I- e; }
results in the highest measured value;5 _: h2 t/ _& A6 k
g) the working voltage between any point in the circuit supplied by the mains and 4 L/ n6 d2 n/ I' [- i. I8 s0 ]– any part connected to earth; and7 ~2 @1 J; P- @3 l0 O% O0 ]6 q
– any point in a circuit isolated from the mains, ) k$ i6 [% n; B! X3 y3 S$ zshall be taken as the greater of the following: i5 G) W Y% v, x3 o! X7 q
– the rated voltage or the upper voltage of the rated voltage range; and % M' S0 b, |8 P! m– the measured voltage; 1 f \: d7 T/ F- S- e' g7 Fh) when determining the working voltage for an ES1 or ES2 external circuit, the normal- i V1 k, V" _2 Z- k' K
operating voltages shall be taken into account. If the operating voltages are not known, the% p& e7 e1 d# T4 C
working voltage shall be taken as the upper limits of ES1 or ES2 as applicable. Short5 Q& l% `2 Q5 o( ?* S% J
duration signals (such as telephone ringing) shall not be taken into account for determining3 j# `. s8 c4 w* r5 ^( Y
working voltage;& J% [2 F* j/ |- F$ y1 W2 t
i) for circuits generating starting pulses (for example, discharge lamps, see 5.4.1.7), the$ G# ]8 k" g& L( l
working voltage is the peak value of the pulses with the lamp connected but before the! i/ R7 Z4 {& I0 Z+ g8 \
lamp ignites. The frequency of the working voltage to determine the minimum clearance 2 @# T1 B( m- P/ H( v" R3 ]$ Ishall be taken as less than 30 kHz. The working voltage to determine minimum creepage ) O1 Q* }7 D$ k. P2 Y$ Ldistances is the voltage measured after the ignition of the lamp.作者: liuqiuhong8888 时间: 2024-3-20 08:54
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