|
4.9 Insulating linings and sleeves3 G' N/ P# y1 Y
4.9.1 Insulating linings and sleeves shall be so designed that they are reliably retained in
" Y/ o+ O$ K" ?" W( |: jposition when switches, lampholders, terminals, wires or similar parts have been mounted.
4 d* m5 B/ X0 ?* N- a; @NOTE Self-hardening resins, such as epoxy resins, may be used to fix linings.
8 J/ W s% O, [+ L f7 |; XCompliance is checked by inspection and by manual test.
+ i9 a* D4 W$ s1 t2 ^; o4.9.2 Insulated linings, sleeves and similar parts shall have adequate mechanical, electrical4 ]9 A! N( F1 E; V
and thermal strength., ~5 k. K6 W- K. c
Compliance is checked by inspection, by manual test and by the electric strength test in; k/ K' s- [& T& y6 F7 N0 l
accordance with Section 10. The thermal properties of wire and sleeve are checked in4 L" @7 L' ]4 p# P7 q
accordance with Section 12. Heat resistant sleeves used as covering for wires attaining a4 C% Z$ @' w! `1 B/ X
temperature exceeding the values given in Table 12.2 of Section 12 shall comply with the
o" ~2 Z9 S! `! C8 J# ]1 |requirements of IEC 60684, taking into account the temperature measured on the wire in/ N. r; P! y. V" ~
question. The sleeve shall be resistant to a temperature exceeding the temperature measured
" {$ I# S" F6 H" ron the wire by 20 °C or withstand the following test:* A" e7 p- n, i8 X
a) Three test specimens of the sleeve, about 15 cm in length, are subjected to the humidity
. Y4 A' C* h# ~% A# Ktest of 9.3 and subsequently to the insulation resistance and electric strength tests' o0 g" p: S' Z- n# \
according to Section 10. A suitable uninsulated copper conductor or metal rod is passed
7 j% Q/ J9 j3 [- I7 wthrough the specimens, and the outside is covered by a metal foil in such a way that no$ U/ y, ]4 G' X' J8 l* Y2 v( U
flashover at the ends of the samples can occur. The measurement of the insulation
1 z( W) n9 f# Z8 |, aresistance and the electric strength test is then made between the copper conductor/metal3 x2 O# V2 U/ A( [
rod and the metal foil.
( h, F$ P* e! |2 b1 u+ j: @- pb) After the copper conductors/metal rods and metal foils have been removed, the specimens
9 b r, f- t% T* f! Bare placed in a heating cabinet for 240 h at a temperature of T + 20 °C, T being the" Y4 L; [- @( @- i- b
measured temperature of the wire.
! R# n5 l8 A5 r- Y% w" T$ r3 rc) The specimens are allowed to cool to room temperature and are then prepared as indicated
# Z- `! x, ], w% p! v: Z+ B$ |under item a) above.
/ s1 j* n3 b- _- r7 fMeasurement of the insulation resistance and electric strength is then made between the; C" G2 O# |6 X2 A* k
copper conductor/metal rod and the metal foil.3 A$ j f$ m2 A, P/ z
Compliance is checked by the insulation resistance values and test voltages specified in
8 }: I( E W6 w4 `( v0 b+ tTables 10.1 and 10.2 in Section 10. |
|