|
|
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。5 P' N( D6 Q) h9 U; E& W( U$ k i
When fitting Y capacitors across barriers, the dielectric strength requirement must be' [: P9 K' q- s4 ?' Q
considered. For example, for voltages in the range of 212 V peak to 354 V peak, two MEANS
2 N1 ^6 D- B8 r4 f. r: D+ C6 j: AOF PATIENT PROTECTION are required to be tested at 4 000 V a.c. This would then require the
( i, Y+ v0 j* Juse of Y1 capacitors. Two Y2 capacitors in series would not withstand this voltage as they are
' A4 Z, `8 I" v2 orated at 1 500 V a.c. each. For voltages below 212 V peak, two Y2 capacitors would suffice as
) _1 e6 e! o) e- {2 Hthe dielectric strength requirement is 3 000 V a.c.
5 N9 W" I0 h0 U+ K e2 Q& y) v. o
A Y capacitor (Y1 or Y2 only) complying with IEC 60384-14 is considered equivalent to one
# _1 q* Q. v9 LMEANS OF PATIENT PROTECTION. Where two capacitors are used in series, they shall be9 x: i. K0 m8 I P6 v2 r
identical in type (either both Y1 or both Y2) and shall have the same NOMINAL capacitance.7 k4 }* D4 T. L) g" P- g" q( J
The capacitor(s) shall meet the dielectric strength for the type of protection for which they are
- ~/ c9 d9 Z; Fbeing used (i.e. one or two MEANS OF PATIENT PROTECTION).
% }2 F3 d& ^* M( {( d
+ Z1 Y# \$ w- l* e: H' _& t3 }Where the working voltage across a barrier forming a MEANS OF PATIENT PROTECTION is less
; H3 |0 O/ L9 \/ H9 c3 ~than 42,4 V peak a.c. or 60 V d.c., a single Y1 capacitor is acceptable for two MEANS OF
$ P. o$ C+ T- W, r8 V" FPATIENT PROTECTION. |
|
/1 
|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
