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17 Overload protection of transformers and associated circuits
. P' }4 Z8 q: G4 N! kAppliances incorporating circuits supplied from a transformer shall be constructed so that in" h" }/ h5 X" [9 U8 g& ~
the event of short circuits which are likely to occur in normal use, excessive temperatures do- V- T7 w+ r; u2 S: W9 t% _- P- o
not occur in the transformer or in the circuits associated with the transformer.9 v% r3 b# P2 m3 W- Z
NOTE Examples are the short-circuiting of bare or inadequately insulated conductors of accessible circuits1 R' n+ l& V, M' i
operating at safety extra-low voltage.6 \: }4 m8 |% d) _0 T! G- j3 F
Compliance is checked by applying the most unfavourable short circuit or overload which is
& k0 M$ Y4 X8 F& hlikely to occur in normal use, the appliance being supplied with 1,06 times or 0,94 times rated
4 F5 J8 w* b- U1 @# Y! r6 mvoltage, whichever is the more unfavourable. Basic insulation is not short circuited.
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3 X7 U8 B) l; @, C6 Z9 L* [& Y特殊标准好像有补充 |
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