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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。
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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)
4 z0 [9 [/ i5 `9 c/ X: c0 sThe term "conductive part" refers to an electrically conductive part that is
+ z4 S$ I+ `% F$ y# e– not normally energized, and- e& ?+ ~; T8 F$ {
– not connected to any of the following:
4 o. @; ?6 i; y7 W) D• a circuit at HAZARDOUS VOLTAGE, or4 q2 V$ \% [; Y B
• an ELV CIRCUIT, or' {" G2 G0 h- j$ v
• a TNV CIRCUIT, or! U. A! `# s0 U# [
• an SELV CIRCUIT, or
1 k; G2 h9 H: b. ?! Y0 M( D• a LIMITED CURRENT CIRCUIT.# x2 t* [" P. U$ G. |+ o
Examples of such a conductive part are the BODY of equipment, a transformer core, and in some cases a
4 U( y4 I# d$ h- H3 H9 I+ ?conductive screen in a transformer.0 s" G! S/ x! B6 e# w
If such a conductive part is protected from a part at HAZARDOUS VOLTAGE by:& |! A7 A- {6 N: Y- S! U) I' T! R
– DOUBLE INSULATION or REINFORCED INSULATION, it is termed a "double-insulated conductive part";; [$ V; B' V, y F' r
– BASIC INSULATION plus protective earthing, it is termed an "earthed conductive part";
) F1 }' _1 N: Y# V3 c4 x _8 _; O– BASIC INSULATION but is not earthed, that is it has no second level of protection, it is termed a "basic-insulated
6 b( \. f2 o2 C! A2 x' Z2 xconductive part".' r/ E# i( c- g3 l5 T3 |6 S
A circuit or conductive part is termed "earthed" if it is connected to a protective earthing terminal or contact in
1 |1 m, ~' k1 A* B; ]such a way as to meet the requirements in 2.6 (although it will not necessarily be at earth potential). Otherwise0 ~* K0 ]. e* n1 ]2 x7 c
the circuit or conductive part is termed "unearthed". |
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