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60950-1中:1 K9 {+ _+ e4 |) ?9 q
Pollution degree 1 applies where there is no pollution or only dry, non-conductive pollution. the pollution has no influence.normally ,this is achieved by having components and subasssembilies adequately enclosed by enveloping or hermetic sealing so as to exclude dust and moistrue2 i! j+ v0 f- v2 W6 V9 g! D* @) [% P
& A7 o$ C6 d; j+ @8 bPollution degree 2 applies where there is only non-conductive pollution that might temporatily become conductive due to occasional condensation. it is generally appropriate for equipment covered by the scope of this standard& p) ~. ]* E6 ]% l+ m; j: \; b
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Pollution degree 3 applies where a local environment within the equipment is subject to conductive pollution, or to dry non-conductive pollution that could become conductive due to expected condensation. |
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