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4.9 Insulating linings and sleeves- F1 ` D# l5 ?4 p& W) n4 w3 J- r
4.9.1 Insulating linings and sleeves shall be so designed that they are reliably retained in
F9 G. i- I) J1 J4 Cposition when switches, lampholders, terminals, wires or similar parts have been mounted.% d* t! g4 _6 Y4 T) S. `
NOTE Self-hardening resins, such as epoxy resins, may be used to fix linings.
3 q0 T* E9 |/ ]1 b# N8 `Compliance is checked by inspection and by manual test.! b0 Y, g* \1 Y$ A9 w
4.9.2 Insulated linings, sleeves and similar parts shall have adequate mechanical, electrical3 g3 n: u" ^" @* ~- K
and thermal strength.
7 C) h X; O6 U0 b& { t' O: d; p6 nCompliance is checked by inspection, by manual test and by the electric strength test in# d! C6 r1 p- k
accordance with Section 10. The thermal properties of wire and sleeve are checked in9 }2 A$ L- r7 s$ V+ P
accordance with Section 12. Heat resistant sleeves used as covering for wires attaining a- V' ?+ `" H6 K# V
temperature exceeding the values given in Table 12.2 of Section 12 shall comply with the
" p. X0 J5 m$ c" Z0 B: p z$ Trequirements of IEC 60684, taking into account the temperature measured on the wire in
7 f5 T* J9 H& h" b* o& c7 hquestion. The sleeve shall be resistant to a temperature exceeding the temperature measured
3 A2 N( ^# Y& i( [" ron the wire by 20 °C or withstand the following test:, H( G, J% O2 g0 r6 c
a) Three test specimens of the sleeve, about 15 cm in length, are subjected to the humidity
. T3 m/ s) r" \6 ?/ Y1 ^test of 9.3 and subsequently to the insulation resistance and electric strength tests# R: S2 f; a9 \3 }7 h8 x
according to Section 10. A suitable uninsulated copper conductor or metal rod is passed# H, \* ^! B* }
through the specimens, and the outside is covered by a metal foil in such a way that no
2 `- t9 R5 E! C) ?flashover at the ends of the samples can occur. The measurement of the insulation
' J7 A+ l; u. j- Zresistance and the electric strength test is then made between the copper conductor/metal6 l! |0 D g* ?! B& p
rod and the metal foil." \# T. Z( t$ J
b) After the copper conductors/metal rods and metal foils have been removed, the specimens& o0 o: G0 w+ i5 E- o3 T6 E. \
are placed in a heating cabinet for 240 h at a temperature of T + 20 °C, T being the4 F: X+ B' T! q- [) ^& u
measured temperature of the wire., O* X! `% N/ G* T1 R1 K
c) The specimens are allowed to cool to room temperature and are then prepared as indicated
. n1 Q5 C& |$ U2 D. I' N1 Sunder item a) above.$ V$ P* q' Z; H4 o1 i! w
Measurement of the insulation resistance and electric strength is then made between the
4 n9 p) r" U9 K1 K. Jcopper conductor/metal rod and the metal foil.( w0 L. f1 V0 R+ u! ?, _ j3 N* a
Compliance is checked by the insulation resistance values and test voltages specified in( W3 r2 G6 [, m9 {7 d
Tables 10.1 and 10.2 in Section 10. |
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