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need to note the clause below:
0 d2 w b8 `+ [ |. I% EIEC60950:8 @ F* `, g: ^6 h( {+ C" C3 R
1.5.9.2 Protection of VDRs
& ?/ b" [2 \3 W wFor protection against
8 v! c- |) G: X− temporary overvoltages above the maximum continuous voltage,
6 d- Z% _& J9 u( }; L" a' E/ a− thermal overload due to leakage current within the VDR, and
6 C3 e! d) d7 \; ^1 a# N− burning and bursting of the VDR in the event of a short-circuit fault,
& ~5 w$ N; F0 Y9 K Fan interrupting means having an adequate breaking capacity shall be connected in series with, G/ l- D, ?1 Z" C0 p2 l
the VDR. This requirement does not apply to a VDR in a LIMITED CURRENT CIRCUIT.7 F9 F/ N5 x }9 F
1 i' }) Z: O* B, ?# V- I
IEC60065:, ]2 b3 i' i: i" _$ h$ c9 i
– thermal stress* v6 X3 }( r! l2 F# G Y
For apparatus with nominal MAINS voltage of <150 V, the apparatus and a test resistor
$ r% l, `3 [% w/ m1 v) f4 Lconnected in series with the apparatus shall be energised from an a.c. source of 250 V.7 p7 @5 Z4 G/ W) i6 J0 A
The voltage source shall be applied for 4 h or until the circuit path through the varistor; U& j7 \2 @9 ~
opens for each of the test series resistance values: 2 000 Ω, 500 Ω, 250 Ω, 50 Ω. A
% \) r: b2 N. A8 ?/ G7 z; hseparate apparatus shall be used for each resistor value, unless damage from the previous" a) d5 c; e" I/ Y" Q
test has been repaired.! r! k8 x C1 t, Q! ?+ E1 e4 v
At the end of each test, the apparatus shall comply with clause 11. |
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