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关于电线护套的厚度测试,请注意,UL2556里面的要求已经修改。近来检查员在核对这个,搞得工厂不明就里。
9 ^- o' b1 w1 \4 u8 p* k4.2.3 Apparatus
$ M9 \! |% @: @e) a dial micrometer having a 6.3 to 6.4 mm (0.248 to 0.252 in) diameter flat presser foot
3 C3 b' S7 C3 n- K2 N# Uexerting a total force of 0.83 ±0.03 N (3.0 ±0.1 ozf) on a rectangular anvil measuring
, \- v) t: a& e4 A; Uapproximately 9 x 2 mm (0.35 x 0.08 in). The face of the anvil on the minor dimension shall be3 r' V1 j# Z( S9 X9 m- @
slightly convex. Alternatively, these measurements shall be made with a dead-weight dial
$ W, R* X1 P# r4 |, ?* B% mmicrometer having a presser foot 6.4 ±0.2 mm (0.248 ±0.010 in) in diameter and exerting a total+ w( ]$ h# B' O4 I: }& V3 z. S
of 85 ±3 gf or 0.83 ±0.03 N (3.0 ±0.1 ozf) on the specimen – the load being applied by means
" {; T- ?' r- r; U# G) a+ fof a weight. The presser foot shall be at least 2 mm (0.08 in) onto the edge of the specimen for
, {+ S9 m! A9 h& H: w: M6 Leach measurement. Micrometers shall have a resolution and accuracy of 0.01 mm (0.001 in); |
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