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4.9 Insulating linings and sleeves! |8 |) J3 y% D- e* l# Z/ D0 x! \2 i
4.9.1 Insulating linings and sleeves shall be so designed that they are reliably retained in
+ Z3 ?+ o8 h$ U3 B4 R* k) Gposition when switches, lampholders, terminals, wires or similar parts have been mounted.
5 h2 }/ p. s+ N6 c4 CNOTE Self-hardening resins, such as epoxy resins, may be used to fix linings.; a1 j" n; B; h a
Compliance is checked by inspection and by manual test.& `8 G4 B# B% b* s
4.9.2 Insulated linings, sleeves and similar parts shall have adequate mechanical, electrical
/ n c- m* p1 eand thermal strength.9 D" a9 C6 e8 j q& s, z; I8 f
Compliance is checked by inspection, by manual test and by the electric strength test in
, x7 [) J+ W7 W+ zaccordance with Section 10. The thermal properties of wire and sleeve are checked in/ L5 |! ~9 o5 E+ C& ^2 p
accordance with Section 12. Heat resistant sleeves used as covering for wires attaining a
. ]% s, k. {; e4 ?, Ytemperature exceeding the values given in Table 12.2 of Section 12 shall comply with the) Q* w# e, \( \
requirements of IEC 60684, taking into account the temperature measured on the wire in
% c$ i" C7 S" v8 m Pquestion. The sleeve shall be resistant to a temperature exceeding the temperature measured
3 t1 [7 T; D& ?3 Fon the wire by 20 °C or withstand the following test:7 p6 }9 @: R- t. H
a) Three test specimens of the sleeve, about 15 cm in length, are subjected to the humidity
0 M6 v. x; b( S' [9 Rtest of 9.3 and subsequently to the insulation resistance and electric strength tests
# M: K; S/ A& {% d, B0 t; ^& t( daccording to Section 10. A suitable uninsulated copper conductor or metal rod is passed
: f( g6 R* i% C& i4 vthrough the specimens, and the outside is covered by a metal foil in such a way that no; X& V6 _8 J0 \& ~6 c8 A
flashover at the ends of the samples can occur. The measurement of the insulation
1 Z, }% p0 h" K( d. \9 Xresistance and the electric strength test is then made between the copper conductor/metal- h5 B" }+ {' P) X# V+ v3 A1 H4 E: k
rod and the metal foil.- Y+ y$ _% R' d# q6 T# ]: w
b) After the copper conductors/metal rods and metal foils have been removed, the specimens$ M. q2 r2 K0 Z
are placed in a heating cabinet for 240 h at a temperature of T + 20 °C, T being the; o" b- `! M9 A5 A- z: v6 w
measured temperature of the wire.( p& ~2 E8 f: H0 j C$ i a
c) The specimens are allowed to cool to room temperature and are then prepared as indicated5 L2 N6 Q# S( M0 @ T
under item a) above.' q( c5 [+ n4 O( _# I
Measurement of the insulation resistance and electric strength is then made between the. b- S* k, W% m" _" y0 i7 S# B W
copper conductor/metal rod and the metal foil.! I0 l2 B" \" A& B# k0 }
Compliance is checked by the insulation resistance values and test voltages specified in
) I+ t9 o' k+ H8 z, {. @# U1 [Tables 10.1 and 10.2 in Section 10. |
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