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增加距离是一种方法,但有时由于产品的实际设计,距离过大又是不允许的.所以对用于整机产品的负离子发生器最好把做成不认为是带电部件: T4 b& k6 P$ T/ D
8.1.4 An accessible part is not considered to be live if
+ B* s% y/ g9 r4 `, S– the part is supplied at safety extra-low voltage, provided that! ]0 h# v* L5 s7 ^# ]& r, w# m
• for a.c., the peak value of the voltage does not exceed 42,4 V,
: }: x- [6 b% y/ w1 D• for d.c., the voltage does not exceed 42,4 V,
( h6 @/ a r" c8 {3 mor
7 m& Z, ^! P/ u( g– the part is separated from live parts by protective impedance.6 F& d1 K' I; m
If protective impedance is used, the current between the part and the supply source shall
! t8 v( k: a( Fnot exceed 2 mA for d.c., its peak value shall not exceed 0,7 mA for a.c. and1 S, a# U/ V/ @# l, t3 D; r
– for voltages having a peak value over 42,4 V up to and including 450 V, the capacitance
8 P& _4 i4 W/ [# _$ Gshall not exceed 0,1 μF,& h$ ] h& T/ s; A6 J! x6 n
– for voltages having a peak value over 450 V up to and including 15 kV, the discharge shall
% T8 R1 e) v8 D7 e+ Knot exceed 45 μC,
7 [1 v2 h/ m8 C& g# I- x7 U1 ~– for voltages having a peak value over 15 kV, the energy in the discharge shall not exceed
; G1 @" S% _8 j; c$ t1 q350 mJ.
7 ]8 k5 @1 |5 p3 u9 u+ wCompliance is checked by measurement, the appliance being supplied at rated voltage.7 F8 h' ^1 j; U; m R
Voltages and currents are measured between the relevant parts and each pole of the supply
4 C3 Y/ Y* ~1 l$ }# `4 g! J+ ksource. Discharges are measured immediately after the interruption of the supply. The! d# }6 ~! N+ F, ?" `/ f6 N8 z, Y3 s5 m
quantity of electricity and energy in the discharge is measured using a resistor having a8 @3 [0 S. k# u6 c: J7 m5 r
nominal non-inductive resistance of 2 000 Ω.' P7 R/ K M, Z* V
结构满足22.27 Parts connected by protective impedance shall be separated by double insulation& Z' @9 X8 A% G* N/ v+ d F. N5 L
or reinforced insulation.
8 @1 ^( `, R; s8 k( l# j+ A* Y8 W22.42 Protective impedance shall consist of at least two separate components whose
5 T( L$ d: r. ]impedance is unlikely to change significantly during the lifetime of the appliance. If any one of
4 W6 X, X* X E6 R, tthe components is short-circuited or open-circuited the values specified in 8.1.4 shall not be
6 v; q! ?) t" m2 m+ C6 H8 u/ yexceeded. |
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