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4.9 Insulating linings and sleeves
% v# c1 a3 T( n9 `5 k4 X2 ?1 Z4.9.1 Insulating linings and sleeves shall be so designed that they are reliably retained in6 h, M8 V2 {2 L+ d# \% y
position when switches, lampholders, terminals, wires or similar parts have been mounted.
. O/ u: E. ^9 H& J3 `) W/ }NOTE Self-hardening resins, such as epoxy resins, may be used to fix linings. z# Q4 N: d: m8 H/ @5 S
Compliance is checked by inspection and by manual test.
' B9 m7 _7 N9 S' F# n4.9.2 Insulated linings, sleeves and similar parts shall have adequate mechanical, electrical: ]' {/ F* |; ]+ q5 E
and thermal strength.
' k+ q8 ]& `1 i0 ?: K; `: gCompliance is checked by inspection, by manual test and by the electric strength test in, `3 H8 ^0 @, `* F2 s# W
accordance with Section 10. The thermal properties of wire and sleeve are checked in0 [9 e+ J8 a" H8 B) H u# i( m
accordance with Section 12. Heat resistant sleeves used as covering for wires attaining a
( e/ w- R) f" G* ^" q8 k" w- _5 W0 Btemperature exceeding the values given in Table 12.2 of Section 12 shall comply with the. v$ h5 O! u U
requirements of IEC 60684, taking into account the temperature measured on the wire in
# V8 E7 _! n' f! p7 squestion. The sleeve shall be resistant to a temperature exceeding the temperature measured& Y% l5 b; D; o
on the wire by 20 °C or withstand the following test:
/ }, m5 f3 }# x5 {9 `' C: ~4 ta) Three test specimens of the sleeve, about 15 cm in length, are subjected to the humidity: K& D8 v6 l, U% F$ Q
test of 9.3 and subsequently to the insulation resistance and electric strength tests: u- ~# A. p2 U/ `4 L3 p
according to Section 10. A suitable uninsulated copper conductor or metal rod is passed* c9 v9 h% h: u' l2 p3 V; c
through the specimens, and the outside is covered by a metal foil in such a way that no
# W% m O/ t# [flashover at the ends of the samples can occur. The measurement of the insulation% R8 J" ^( I3 ]* e3 P$ G' Y& j
resistance and the electric strength test is then made between the copper conductor/metal
& ~4 l/ Z* ?3 jrod and the metal foil.
) Q$ V9 p* f9 T8 H# _- c1 Y4 J/ cb) After the copper conductors/metal rods and metal foils have been removed, the specimens
" G* r6 B! F: lare placed in a heating cabinet for 240 h at a temperature of T + 20 °C, T being the( A# D1 n8 q8 l# A# k0 Q$ k
measured temperature of the wire.
* p4 D* l3 V5 B zc) The specimens are allowed to cool to room temperature and are then prepared as indicated
, R6 V3 `) {" Q$ j- x7 D ~; funder item a) above.
6 _0 f; e, J9 ]5 `5 ], vMeasurement of the insulation resistance and electric strength is then made between the
1 a* d8 W* W8 w5 w$ |* @copper conductor/metal rod and the metal foil.
7 u6 U, u4 j0 y5 }Compliance is checked by the insulation resistance values and test voltages specified in
4 \; Q0 t' g0 K8 ETables 10.1 and 10.2 in Section 10. |
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