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变压器磁是可以做为初级元件来处理的,这种情况多用于开关电源产品内的高频变压器。$ G( H% O! H1 J; B8 P
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在标准中的Table 2H中有对此种情况进行了说明。见下文(摘录于标准)
) r0 Y/ _9 u* m9 ]The term "conductive part" refers to an electrically conductive part that is1 K7 {8 _1 r- C1 H* L- \- N9 {
– not normally energized, and( X! b) C$ E0 S0 U9 x
– not connected to any of the following:+ l t% `' ?9 g9 ?! w" E, ^* C
• a circuit at HAZARDOUS VOLTAGE, or: n5 d0 u) ^2 [1 C2 i
• an ELV CIRCUIT, or1 M9 g" D) d/ |9 R4 u' u
• a TNV CIRCUIT, or# g& K8 c! j4 N6 M) J& c0 t
• an SELV CIRCUIT, or* ]0 T. }; N5 f" v; ?8 H2 Z
• a LIMITED CURRENT CIRCUIT.8 w s3 z0 g3 w
Examples of such a conductive part are the BODY of equipment, a transformer core, and in some cases a
( ]0 K# H; @# Y# J% H7 I: rconductive screen in a transformer.) q8 F: f9 p* u" s" [# ]' E
If such a conductive part is protected from a part at HAZARDOUS VOLTAGE by:
' Q6 H2 u6 G! H– DOUBLE INSULATION or REINFORCED INSULATION, it is termed a "double-insulated conductive part";
K) i6 g" E6 m9 s1 k. |: ]– BASIC INSULATION plus protective earthing, it is termed an "earthed conductive part";! ]3 O5 [5 V7 }4 ^* Z$ C, K6 l
– BASIC INSULATION but is not earthed, that is it has no second level of protection, it is termed a "basic-insulated
9 |% X L% H8 tconductive part".2 l9 K; j& Z7 w% B9 L3 g& E( p
A circuit or conductive part is termed "earthed" if it is connected to a protective earthing terminal or contact in
% |2 C7 T" U) ^! psuch a way as to meet the requirements in 2.6 (although it will not necessarily be at earth potential). Otherwise
$ a" W6 e/ A/ n w# Q& L5 v0 Hthe circuit or conductive part is termed "unearthed". |
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