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這里第一版標準和第二版標準在Clearance上的算法有很大的不同,舊標準一般不用內差法即可,但新標準是需要的 請見下面此處的對比:
% [! b% W: o. A8 s. F' bFor PRIMARY CIRCUITS operating on nominal AC MAINS SUPPLY voltages up to 300 V, if the PEAK WORKING/ R) `$ r/ r' e
VOLTAGE in the circuit exceeds the peak value of the AC MAINS SUPPLY voltage, the minimum" l. R* S& Z- A4 e. k7 x/ I- H
CLEARANCE for the insulation under consideration is the sum of the following two values:0 j1 W3 u' q7 `6 e
– the minimum CLEARANCE value from table 2H for a WORKING VOLTAGE equal to the AC' @8 \6 M7 I. {% B: t- |8 T0 g" G
MAINS SUPPLY voltage; and
8 l1 Q* e/ M3 B* y7 r: K9 i" M0 T– the appropriate additional CLEARANCE value from table 2J.8 [- T: C# \6 w* C3 H. S
(舊標準)' w/ `- h0 B* G
For an AC MAINS SUPPLY not exceeding 300 V r.m.s. (420 V peak):9 p! T$ b# d: v' S J. M& X; V
a) if the PEAK WORKING VOLTAGE does not exceed the peak value of the AC MAINS SUPPLY
2 @' g. g+ M; t0 bvoltage, minimum CLEARANCES are determined from Table 2K;
5 z5 m8 t2 A* a( ]2 Wb) if the PEAK WORKING VOLTAGE exceeds the peak value of the AC MAINS SUPPLY voltage,
" I$ W* G- X; K$ N: U3 ~5 s4 r4 uthe minimum CLEARANCE is the sum of the following two values: D" p% ~. [1 F" w: j& k" I, t
• the minimum CLEARANCE from Table 2K; and
( e b2 U+ L' u9 Q( V+ h. e• the appropriate additional CLEARANCE from Table 2L% u# C! e3 |# ?$ E
(新標準)
0 _' d- }2 l1 M' V+ A所以Clearance相對新標準嚴苛些了. |
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