标题: UL153 带电部件的可触及性 [打印本页] 作者: yyrwj 时间: 2015-2-13 11:13 标题: UL153 带电部件的可触及性 24 Electrical Spacings0 \- ~$ |+ u. x2 X5 N/ O7 `
24.1 The spacing between uninsulated live parts of opposite polarity, and between uninsulated live parts& B+ G# {9 i, f2 [; ^
and metal that is capable of being grounded shall not be less than 1/4 inch (6.4 mm) through air or 3/8 ' K. u4 Z5 H1 V4 C0 o9 W: V. p% Oinch (9.5 mm) over surface. The outer wrap of an open core and coil ballast is determined to be an * S; j9 N5 W5 B& c! Iuninsulated live part with respect to this requirement. ' \) x5 L5 s6 W3 mException No. 1: The spacing requirements do not apply between uninsulated live parts of a wiring device, # p$ y; N0 w$ u5 ~& \( dsuch as a lampholder or switch, and dead metal that is part of the wiring device and including mounting - \2 K/ A0 J7 G+ Rscrews, rivets, yoke, clamp, or similar components; or for a portable luminaire provided with a grounding# @: }/ d7 @: o8 R
means between such live parts and that part of the dead metal surface of the portable luminaire on which - S! h& n# h- `5 w: H! bthe device is mounted in its intended manner. See Figure 24.1., X0 s9 j* u n$ s# N3 V3 @
Exception No. 2: When an isolated dead metal part is interposed between or is in close proximity to:! K( u G' v/ q2 c( ?* `3 R, j
a) Live parts of opposite polarity; % { C/ ~0 T! X( Fb) A live part and an exposed dead metal part; or6 @. U1 Z9 N5 {3 D" s# s* r* p
c) A live part and a dead metal part that is able to be grounded, the spacing shall not be less + }# H G4 x( H7 v& u# q/ T+ Vthan 3/64 inch (1.2 mm) between the isolated dead metal part and any one of the other parts * C/ p( G' j" Gpreviously mentioned, provided the total spacing between the isolated dead metal part and the/ U# u8 i0 Q/ w, N0 _
two other parts is not less than 1/4 inch (6.4 mm) through air or 3/8 inch (9.5 mm) over surface.( @ h e8 H6 u& @; Z
Exception No. 3: The spacing between uninsulated live parts of a Class 2 circuit and between such parts9 k; z6 l4 g* L7 o: B, ?
and dead metal that is grounded in service is not specified. 1 ^2 X! \' Y! a" W" \8 Q4 m5 q x/ b/ Q N; F
各位大侠，UL153这章的dead metal part,是不是可以直接理解为非金属部件？ r6 P* r9 {7 ]! w& C: N1 S作者: Nezof 时间: 2015-2-13 11:17
是金属部件作者: yyrwj 时间: 2015-2-13 11:22
直接理解为金属部件？那前面这个DEAD没意思了？作者: robin_he 时间: 2015-2-13 11:27
