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電線電纜網(wǎng) > 國(guó)外線纜 > Permitivity test(許可試驗(yàn))(完整版)

Permitivity test(許可試驗(yàn)) - 無圖版

下雨星 --- 2008-11-19 18:47:43

1

帶“W”戶外使用的PVC絕緣線將要求做Permitivity test(許可試驗(yàn))。

 請(qǐng)問各位,這個(gè)Permitivity test(許可試驗(yàn))具體是什么?

陳彬 --- 2008-11-21 10:32:48

2

5.2.4 Permittivity and stability factor
5.2.4.1 Permittivity –″W″ Type cords
5.2.4.1.1 When tested in accordance with CSA C22.2 No. 0.3, Clause 4.28.4; UL 1581, Section 1020; or NMX-J-040-ANCE, the permittivity of the insulation shall be as follows:
(a) after 14 d of immersion the capacitance shall not be more than 10% greater than the capacitance measured after the first day; and
(b) after 14 d of immersion the capacitance shall not be more than 3% greater than the capacitance measured after 7 d.
5.2.4.1.2 Tests shall be made using three 5 m (16 ft) specimens of insulated conductor. Specimens shall be
(a) tested without any polyester tape or similarly non-absorptive separator; and
(b) selected before assembly into finished cord.
The middle 3 m (10 ft) of each specimen shall be immersed continuously in tap water in a temperature of 50 °C ± 1 °C for thermoset insulation or 60 °C ± 1°C for thermoplastic insulations for 14 d. The1m(3ft) end portions of each specimen shall be kept dry above the water as leakage insulation. A cover for the tank shall be placed directly above the surface of the water. The water level shall be kept constant. 

電容的變化率  (C14-C1)/C1<=10%    (C14-C7)/C7<=3%

[陳彬 在 2008-11-21 10:44:36 編輯過]

MartinPeng --- 2008-11-21 16:27:21

3

指水中電容率和穩(wěn)定因素測(cè)試.很多"W"料目前還通不過,國(guó)內(nèi)沒有合格的測(cè)試試備,所以UL 現(xiàn)在還沒有非常強(qiáng)調(diào)要強(qiáng)執(zhí)抽檢.
-- 結(jié)束 --