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请问 IEC 60950-1 Clause 4.3.7 该如何理解 ?
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标准是要求接地的部份需要装上温度保护器吗 ?6 z1 X4 o9 W c, L# a4 i
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4.3.7 Heating elements in earthed equipment0 i9 H: B! W; K y3 @) n
Heating elements in equipment that is earthed for safety purposes shall be protected so that,/ X9 |: j, a1 T1 b- E
under earth fault conditions, a fire hazard due to overheating is prevented. In such equipment,0 P& o C& H6 Z+ C+ H- Q3 F# Z
temperature sensing devices, if provided, shall be located in all line conductors supplying the% l; m# G' h% u$ c4 T8 P1 I6 p
heating elements.3 O1 v6 B# C) f9 k; P/ u
The temperature sensing devices shall also disconnect the neutral conductor for each of the
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a) in equipment supplied from an IT power distribution system;
8 f5 [; P; i9 ~7 cb) in PLUGGABLE EQUIPMENT supplied through a reversible appliance coupler or a reversible2 [! [) z8 C/ N- p2 S
plug;
1 e" Z4 r" K7 C% h; nc) in equipment supplied from a socket-outlet with indeterminate polarity.
o7 i$ D4 ^- j( e; p( e6 cIn cases b) and c), it is permitted to meet this requirement by connecting a THERMOSTAT in one" A# Z) W4 \$ W/ X: L- a# N: v
conductor and a THERMAL CUT-OUT in the other conductor.
' x8 b8 F- s0 U5 @* \5 Y# yIt is not required to disconnect the conductors simultaneously. |
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