|
19.5 The test of 19.4 is repeated on class 0I appliances and class I appliances
4 X; D9 j! N( b; `incorporating tubular sheathed or embedded heating elements. However, controls are not
9 @1 M# ]( r: \: }+ kshort-circuited but one end of the element is connected to the sheath of the heating element.
- [9 D# k& k% H& O" s& O) MThis test is repeated with the polarity of the supply to the appliance reversed and with the 0 Q P/ C! a! F6 v7 g. B: l+ Y' b
other end of the element connected to the sheath. 1 d, k+ E0 F) {7 y; X2 b
The test is not carried out on appliances intended to be permanently connected to fixed wiring
: }7 g/ T% r, `and on appliances where an all-pole disconnection occurs during the test of 19.4.
; b* V6 J. t& N1 x# PAppliances with a neutral are tested with the neutral connected to the sheath.
3 Q- P5 b3 J0 [) g/ F nNOTE For embedded heating elements, the metal enclosure is considered to be the sheath.0 r" s* g0 e1 \8 v+ h
什么意思三相三线的取暖器需要测试吗4 `: A' U1 t4 W$ L0 L
怎么测试
- E; K& [0 b) g1 o* o |
|