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请问 IEC 60950-1 Clause 4.3.7 该如何理解 ? - F1 B& R- O! ~ X- o7 P2 g
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标准是要求接地的部份需要装上温度保护器吗 ?) a* d5 }2 M6 x" K$ `' }8 G
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6 I- p% l/ G. X/ E7 P; B; m9 z4.3.7 Heating elements in earthed equipment
# S5 N3 P$ u7 i% ?9 A7 G7 dHeating elements in equipment that is earthed for safety purposes shall be protected so that,
. j9 I# u* @, M& dunder earth fault conditions, a fire hazard due to overheating is prevented. In such equipment,
7 @$ V7 h0 p5 @! `; k7 h4 Gtemperature sensing devices, if provided, shall be located in all line conductors supplying the0 G5 J: v9 N9 `4 L# D, M
heating elements." K. X, G# i( g" M) \
The temperature sensing devices shall also disconnect the neutral conductor for each of the# H" H" w' K+ W |) E
following cases:# W1 @" p- H! e) j# }8 B2 [0 ~
a) in equipment supplied from an IT power distribution system;
i" ~5 A% I2 Pb) in PLUGGABLE EQUIPMENT supplied through a reversible appliance coupler or a reversible" [, q4 v) n! O) v
plug;9 ~3 s- }+ L/ h- f5 B* |
c) in equipment supplied from a socket-outlet with indeterminate polarity.4 _/ p: o. q) H6 t! X7 f- w
In cases b) and c), it is permitted to meet this requirement by connecting a THERMOSTAT in one( e1 ^* S( w; R# p5 a) u6 L
conductor and a THERMAL CUT-OUT in the other conductor.6 H% ^$ E4 w7 Z5 v
It is not required to disconnect the conductors simultaneously. |
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