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1. UL1310 固有限制,非固有限制区别?
! [; A6 `% U$ G9 ~! x2. 什么是 energy limiting impedance?
5 m' U# {% }" q; G3 b30.2 Inherently limited
) L5 ?. o9 k; w3 ~; t/ ^30.2.1 Under any condition of resistive loading – including short-circuit and interconnection of outputs
: r' l# R% {/ Q; O* Ywhen not prohibited by marking – the maximum output current shall not exceed the value specified in
* b s/ f7 c0 S: V% R- ]/ H Q+ ATable 30.1 and the maximum output volt-amperes shall not be more than 100 volt-amperes, except as+ r' \+ v- p' h$ V( E k
indicated in 30.2.3 and 30.3.1, for the following conditions, as applicable:; N. o: [& T& V5 q4 L1 \/ U
a) For a unit which employs a transformer with no form of protection, the measurement is to be1 q+ F. k7 P# `6 B/ d0 y
made 60 seconds after the unit is connected to the source of supply.% F4 a( N1 W8 o
b) For a unit which employs a transformer and an energy limiting impedance or energy limiting. K, d( l. U" M. T
circuit (a resistor, a PTC device, or similar circuitry) required for the purpose (See 2.8), the( F6 c, s3 k. ^ U7 K4 u" c/ d3 x
measurement is to be made five seconds after the unit is connected to the source of supply.
+ d2 ?. R- {: x6 g: Jc) For a unit which employs a transformer and either a thermal cutoff, a fuse, or both, all7 _4 F2 x% z8 ?$ z; E4 H
protection is to be defeated during the test and the measurement made 60 seconds after the
( \4 l! c9 I& G6 Z) cunit is connected to the source of supply.
! S# v' }" {' E+ z0 \0 \- zd) For a unit that employs a transformer and a combination of a limiting impedance or circuit
8 l! V- O! I4 C) q4 [required for the purpose, and a protective device (such as a thermal cutoff, a fuse, or both), all
- z! f9 T. [1 E [protective devices are to be defeated and the measurement is to be made five seconds after ^" ?; @% b, h( \0 M
the unit is connected to the source of supply.
6 _ ]2 b) \$ q1 u$ \- he) For a unit that employs a dc input, in accordance with 1.1, and a combination of a limiting
) u- ^8 w2 m( k( c- _( N- h! Kimpedance or circuit required for the purpose, and a protective device (i.e. thermal cutoff, fuse,
2 `2 ]; U8 u$ M% h. [: Por both), the protective device is to be defeated and the measurement is to be made five( p: a! _2 k) a+ o) V
seconds after the unit is connected to the source of supply." B" ^! X G! A9 k- L: _5 T9 C
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