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请问如下这个测试怎么做啊
( C/ [$ K y C! w# t9 {1 D18 Limited Short-Circuit Test
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18.1.1 Following the test specified in 18.2.1 or 18.3.1, a thermistor shall:
0 P0 W# t5 d; n5 Ea) Comply with the requirements in 11.1.2 or be in a permanently high resistance state; and+ \7 |+ S) c* V; O% @
b) Complete the test without igniting the cotton indicator or opening the ground fuse described in3 m3 R- U; Z& T) o
18.1.4 and 18.1.5.2 n, Z; i% v2 l
18.1.2 When the results of the Limited Short-Circuit Test on the thermistor itself comply with 18.1.1, the
, A, o2 o1 C5 _$ a8 Vtest is not required to be repeated during the investigation of the end product.
: g7 Z: x8 L! f! B# E5 I18.1.3 Three samples of a control thermistor are to be subjected to this test. The test is to be conducted
9 a( X) ^3 `! Q# F$ x3 mat rated voltage (Vr).7 N$ X' N# _' M7 ]+ a& n
18.1.4 A ground fuse is to be connected between the metal enclosure, metal mounting surface, or metal
4 a# K( N- m. O; \" Cscreen described in 18.1.5 and the unswitched line to indicate an arc-over to the enclosure or mounting, }/ l' _% e1 K/ p6 Q
surface. Where each line is switched, the fuse is to be connected between the enclosure, mounting# b' ?# g# R% e [
surface, or screen and the live pole least likely to arc to ground. The fuse is to be a 3.0 A nontime-delay
7 ^5 L$ a& n2 bfuse having a voltage rating not less than the rated voltage (Vr) of the thermistor.
M& T F* y; x# V# N4 I. i$ N. I9 h18.1.5 Cotton not less than 12.7 mm (1/2 in) thick is to surround a metal screen enclosing the thermistor
0 ?+ R2 a) W# f) Yat a distance not more than 12.7 mm from all parts of the thermistor.
* ?; @" O+ e) d$ Z18.1.6 The cotton is to be surgical cotton, such as commonly used for medical purposes. |
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