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xiaodeng 发表于 2016-12-10 13:31
1 R- t8 k5 x! b* D& g这点就不用考虑了。 如果即使短路, 也有保险丝保护。 只考虑保险丝前端就好!
& J8 x6 _; d/ f& `5 Y24 Spacings: a: n% c8 ?! q0 V
24.1 Spacings between live parts of opposite polarity, between live and dead metal parts, and between live parts and a metal enclosure, shall be as specified in Table 24.1 or Table 24.2, as appropriate. If a live part is not rigidly secured in position by a means other than friction between surfaces, or if a movable dead metal part is in proximity to an uninsulated live part, the construction shall be such that at least the minimum spacings will be maintained.
! i; t2 S% N S& a! [2 N! }# jException No. 1: Spacings between traces on a printed-wiring board need not comply with Tables 24.1 and 24.2 if the printed-wiring board complies with the abnormal operation test in 39.8. See also 22.3. The requirements specified in 22.3 and 39.8 do not substitute for the minimum required spacings between the printed-wiring board foils and dead metal parts or the spacings between the primary and secondary foils of the printed-wiring board as specified in Table 24.1 or 24.2.. ]4 N7 ?; v1 @2 s9 v5 c' |' s
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: s2 {. i* T. d5 ^3 u0 t39.8.3 Operation of an overcurrent protective device other than the branch circuit overcurrent protective device is acceptable.9 d% b8 ?# O- O" K
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