|
参考一下UL2021:
8 p8 Q% x+ k2 ~! G5 b* H15.2 Protection of wiring* r( {% L* S3 Y j! i
15.2.1 The wiring and connections between parts of a heater shall be protected or enclosed, except that
7 x# F4 b) u* A; sa length of flexible cord may be employed for external connections, or for internal connections that may
6 G5 R( C. w' E2 s2 P( kbe exposed during servicing, if flexibility of the wiring is essential.
9 `& K& w" k8 V, v15.2.2 The internal wiring of a heater in the vicinity of a lampholder that accepts either an infrared lamp
: _: W8 b" |+ i# P# T) Tor an ordinary lamp:
V. K) d; |2 m) i, p- Ja) Shall be a jacketed type at least equivalent to Type SP-2 flexible cord. Asbestos-insulated1 N- C( c& _& j5 R1 m6 v: _8 i; B; K
wiring and appliance wiring material is not acceptable unless provided with sleeving or tubing.6 [0 @' u8 T& F* V" C2 |' W. b
b) Shall be routed along the metal surface of the heater enclosure and shall be so secured as: M! _- F& M3 F* i) J2 ?; v1 a* `
to minimize the likelihood of its being hooked or grasped.
3 N/ e+ M+ R9 n$ _5 V15.2.3 A conductor utilizing beads for insulation shall not be used outside an enclosure.7 r. Y" \: }+ B- f! [
15.2.4 Internal wiring that is exposed through an opening in the enclosure of a heater is considered to be
) i5 @) }7 A. b tprotected as required in 15.2.1 – 15.2.3 if, when judged as though it were film-coated wire, the wiring
5 v2 E2 Z: E, pwould be acceptable according to 7.17– 7.20. Internal wiring within an enclosure is acceptable if, even
0 l m3 D$ z. cthough it can be touched with the probe, it is so protected or guarded that it cannot be grasped or hooked
. x! _( S# C% a }% Xin such a manner that it could be subjected to stress. |
|