DSH 394A Touch current for equipment having multiple supplies supplying power

小米

广东安规检测
有限公司提供：

小型摆管淋雨试验机

IPX5X6X7喷水试验机

1000L恒温恒湿箱

各种试验指现货

可程式恒温恒湿试验箱

水平垂直燃烧机

自动卷线器试验机

耐划痕试验机

各种灯头量规现货

灼热丝试验机现货

GB1002插头量规

IPX1-X7淋雨现货

IEC61347/UL935镇流器热试验箱

灯具防风罩

IK冲击试验机

UL498插头插座量规

VDE0620插头插座量规

稳定性试验台

家电温升测试角

针焰试验机现货

热电偶焊机现货

家电125mm试验指

E12灯头量规

无绳壶无绳电熨斗插拔寿命试验机

IEC60335试验指甲

DSH 394A & @$ p9 C5 y' Z . q3 }9 b# r$ _( v $ `* L1 x: k% L

Touch current for equipment having multiple supplies supplying power simultaneously

5.1.2, last paragraph / 5.1 1 G% i, t* `  W% y8 v$ Q5 g

60950-1(ed.1) & 60950(ed.3) ( a! w% ]+ ~! _; d3 N

Standard(s):
IEC 60950 (1999) 3rd Ed.
) M+ X+ k8 j. pIEC 60950-1 (2001) 1st ed.
) w5 R: H. u; x: \3 _7 n: f* qSub clause(s):
5.1.2, last paragraph
5.1
  t& w( w, v$ g- c' rSheet n°: 394A
Subject:
9 u; x+ i( W) D) [$ I( GTOUCH CURRENT for equipment
7 R  D7 S( K9 y* S/ a9 i5 x4 ~having multiple supplies supplying
8 d$ e- c( g* [  i2 n( W& y: tpower simultaneously
Key words:
- TOUCH CURRENT for equipment
( n5 w& J1 B& L# l4 p& Rwith multiple supplies
Decision taken at the 41st
9 K; {' i+ N, W3 d7 J. GCTL meeting 2004. This
3 U1 M6 j3 r- u# o) T* j, jdecision replaces n. 394
taken at the 39th CTL
, S* v2 a& z6 ]9 A4 [5 l" B, [9 B0 Gmeeting 2002
3 T+ P4 H5 W& VQuestion:
2 J0 r( x2 b/ C" e$ e9 d  F( ?% ^  ?1. Should the TOUCH CURRENT be measured for each individual supply source to determine if the
PROTECTIVE CONDUCTOR CURRENT exceeds 3.5 mA and if it does exceed, then require PERMANENT
or PLUGGABLE TYPE B connection to the supply and meet 5.1.7?
8 |. {! V# _6 V. L2. Should the cumulative TOUCH CURRENT be measured to determine if the total TOUCH CURRENT
exceeds 3.5 mA? If the total TOUCH CURRENT does exceed 3.5 mA then require that AC MAINS
7 Y0 w# P# L1 L& Q% USUPPLY to be connected to separate AC MAINS SUPPLY circuits with at least one source having a
- m1 Y2 C8 k7 x& d# M5 ?& Nreliable connection to PROTECTIVE EARTH (e.g. be PLUGGABLE TYPE B or PERMANENTLY
connected EUT?
Rationale:
PLUGGABLE EQUIPMENT TYPE A does not have a reliable connection to building PROTECTIVE EARTH. Therefore, if
7 d. V. u4 l  `  H. L$ wthe TOUCH CURRENT measurement exceeds 3.5 mA, then that particular source needs to be PERMANENTLY
, b) y2 f% i' Wconnected or have a PLUGGABLE TYPE B connection to PROTECTIVE EARTH. In older buildings, EARTH may
not be present on the PLUGGABLE TYPE A socket outlets on the wall. The multiple connection does not help, as all
8 A" d. M6 j( S- r8 ]such socket outlets may not have EARTH connection. Therefore, if the individual or cumulative PROTECTIVE
/ y5 t$ `; h) q# LCONDUCTOR CURRENT exceeds 3.5 mA, then at least one of the sources needs to be PERMANENTLY connected or
have a PLUGGABLE TYPE B connection to PROTECTIVE EARTH. If one of the sources is required to be
# w* S" A/ [$ q8 u9 OPERMANENTLY connected or have a PLUGGABLE TYPE B connection to PROTECTIVE EARTH in order to
comply with the TOUCH CURRENT requirements, the equipment shall be provided with both a marking on the equipment
and a statement in the installation instructions, specifying that the USER is to disconnect all power sources connection
4 w# M4 ?" b# T% _, y& \* w# r  ^* Tbefore disconnecting the PERMANENT connection or the PLUGGABLE TYPE B connection
( h" R% n: b* ?" t" Z3 LDecision:
See copy of the CDV for IEC 60950-1 2nd edition on Page 2
. o3 o. E% C& B' F  M
! ?$ C& u# [$ ?  u2 W- K
1 J* ?2 j9 ]3 V. N+ y