引用第47楼dzxtt于2007-08-12 13:24发表的:
热延伸是否是线材老化后的伸长率呢？标准里有规定的啊
热延伸是针对材料的测试,不是老化后的伸长率,他是要求在一定的温度下对试样施加一定的机械负荷,等到规定的时间以后测量负荷下的伸长和撤去负荷的伸长,与原试样的长度之比!
有的也叫加热变形试验-----实际与楼上李兄说的是一样的;
例如--UL62规定:
NMX-J-191
Heat Deformation of Semiconductive Shielding, Insulations and Protective Coverings of Electrical
Conductors – Test Method
5.1.3 Deformation
5.1.3.1 Insulation
The insulation on single-conductor wires, and on the individual conductors (separated, in the case of
parallel cords), shall not decrease by more than 50% in thickness when subjected to a force caused by a
mass as shown in Table 40, and while maintained at the temperature shown in Table 40 for 1 h.
5.1.3.2 Jacket
Smoothed specimens of jackets from finished cords and cables shall not decrease by more than 50% in
thickness when subjected to a force caused by a mass of 2000 g, and while maintained at the temperature
shown in Table 40 for 1 h.
5.1.3.3 Method
Compliance with Clauses 5.1.3.1 and 5.1.3.2 shall be determined in accordance with the method
described in CSA C22.2 No. 0.3, Clause 4.3.6.1; UL 1581, Section 560; or NMX-J-191-ANCE.
有沒有誰比較了解HPN線材的耐電弧測試的呢?說說吧!
引用第53楼wangrang于2007-08-29 13:28发表的:
有沒有誰比較了解HPN線材的耐電弧測試的呢?說說吧!
参照UL62 第 5.2.5~5.2.6条.UL62-2006版第49页.~呵呵~
5.2.5 Standard arcing test for Type HPN
5.2.5.1 General
Type HPN cord shall not arc when a specimen of finished cord is connected at one end to a 120 V (rms)
source of supply through a 15 A fuse or circuit breaker and subjected to a standard test flame applied 13
mm (0.5 in) from the other end of the specimen for 2 min. Compliance shall be determined in accordance
with the method described in Clause 5.2.5.2; CSA C22.2 No. 0.3, Clause 4.28.12; or UL 1581, Section 1670.
5.2.5.2 Test method
The specimen for test shall be of any suitable length. One end shall be cut off square, care being taken
that the conductor ends are flush with the cut end of the cord. The cord shall be laid across a
nonconductive surface, the square cut end protruding approximately 0.1 m (4.0 in) beyond the surface
edge. The opposite end shall be connected to the voltage source between the conductors of a
two-conductor cord and between the circuit conductors joined together and the grounding conductor of a
three-conductor cord. Using a Tirrill, Bunsen, or similar appropriate gas burner, a standard test flame (as
described in Clause 5.1.5.1) shall be obtained. With its barrel vertical, the burner shall be placed under
the free end of the cord with the tip of the inner blue cone touching the flat underside of the specimen
midway between the conductors and 13 mm (0.5 in) from the square end for a 2 min period. The cord
does not comply if arcing occurs between the conductors during application of the flame or if the fuse or circuit breaker opens.
=======================
5.2.6 Flex arcing test for Type HPN
===========================
5.2.6.2 Procedure
The procedure shall be as follows:~
標準有看過，其實只是沒有看過具體的測試，有點抽象...
呵呵，謝謝拉!
我搞PVC电缆料，不知有什么可以帮上忙
只要与UL电源线有关的测试疑问和经验,大家都可以在这里交流的!但是最重要的还是讨论实际测试方法和手段与标准的理解 !
引用第43楼cableyzf于2007-08-10 14:31发表的:
对，是最小截面积（最小厚度乘以宽度），平时都没注意。虽然UL1581没说，我查了一下JIS有规定最小厚度（JIS要求至少要测五个值）乘以宽幅得出截面积。检测标准这部分真的是越抠越细，所以这部分的讨论太重要了。谢谢版主！
ＵＬ１５８１中有规定的：在标志线处，标志线内６ＭＭ及１９ＭＭ处共测试４点取最小值－－440.24 The thickness of the specimen is to be taken as the smallest of four measurements to 0.001 inchor 0.01 mm, two of which are to be made at 1/2-inch or 13-mm intervals between the bench marks on oneedge beginning 1/4 inch or 6 mm from either mark, with the other two measurements being made at corresponding points on the opposite edge.
对于UL 可能是我最熟悉不过的,我们公司实验室申请的UL758,UL62,UL1581的目击测试已于2008年9月15日完成.是全球唯一一家可以做目击测试的公司.刚来公司,希望和大家交流交流.
学习学习，我才作过两个电线的案子。
