|
|
老师说的很对，不过A1里面对这块作了适度修正，写得更合理了，主要还是要根据两端的工作电压来判定。
; ^* E2 Z9 f* h* |" L% n. @9 cWhen fitting Y capacitors across barriers, the dielectric strength requirement must be9 y( e8 E# [: {( ~1 L
considered. For example, for voltages in the range of 212 V peak to 354 V peak, two MEANS& O Q0 O3 l* V' u3 _
OF PATIENT PROTECTION are required to be tested at 4 000 V a.c. This would then require the8 y U' ^* i7 I, s
use of Y1 capacitors. Two Y2 capacitors in series would not withstand this voltage as they are4 e# ~/ l5 k7 ^2 Y. \1 S
rated at 1 500 V a.c. each. For voltages below 212 V peak, two Y2 capacitors would suffice as% w! H# M1 ^" g% H0 l/ q
the dielectric strength requirement is 3 000 V a.c.
: f \- p4 u- c! }( `+ L
" Z5 c2 P K3 l) z! i/ o- EA Y capacitor (Y1 or Y2 only) complying with IEC 60384-14 is considered equivalent to one
) }8 y% I! e) BMEANS OF PATIENT PROTECTION. Where two capacitors are used in series, they shall be6 n: C( {! H7 [/ C5 l
identical in type (either both Y1 or both Y2) and shall have the same NOMINAL capacitance.
% u8 c# s0 F yThe capacitor(s) shall meet the dielectric strength for the type of protection for which they are
/ T* c8 {& L- ^3 ?! ^2 \9 ebeing used (i.e. one or two MEANS OF PATIENT PROTECTION).3 w3 B) v* _3 r3 X2 f, g6 ?; }
# ^! X/ G. T9 X' T: q6 {/ `Where the working voltage across a barrier forming a MEANS OF PATIENT PROTECTION is less
* r( G o9 M- ~- wthan 42,4 V peak a.c. or 60 V d.c., a single Y1 capacitor is acceptable for two MEANS OF
* |- S& O+ q/ z Z! m5 gPATIENT PROTECTION. |
|
|关于安规|小黑屋|安规QQ群|Archiver|手机版|安规网
( 粤ICP13023453-10 )
窥视卡
雷达卡
发表于 2012-4-21 08:13
显身卡