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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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, T4 O. \( r, j" e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)
' |! X0 |5 c# H- lThe term "conductive part" refers to an electrically conductive part that is
) \, j {, y; J- h. T– not normally energized, and8 f P) U: v# k/ S+ f- }! ?
– not connected to any of the following:
+ j5 h6 X7 s( ?# n* Y2 ]1 `$ m1 B• a circuit at HAZARDOUS VOLTAGE, or
n9 J! ?# o+ Y: d$ [• an ELV CIRCUIT, or1 E7 |$ g7 c2 M0 `
• a TNV CIRCUIT, or
+ M( e# q: ]0 |( P2 ]• an SELV CIRCUIT, or
! y& ~( P; I) t+ r) Y' N$ J [• a LIMITED CURRENT CIRCUIT.
- |9 J2 [! [2 r0 YExamples of such a conductive part are the BODY of equipment, a transformer core, and in some cases a
: Y h6 W1 Y7 z1 h; ~5 pconductive screen in a transformer.0 S& v1 t7 ?( K# Q8 \
If such a conductive part is protected from a part at HAZARDOUS VOLTAGE by:
7 Z5 i4 \* B o; K– DOUBLE INSULATION or REINFORCED INSULATION, it is termed a "double-insulated conductive part";
" }: v$ h2 k, M; F9 O7 Q) w– BASIC INSULATION plus protective earthing, it is termed an "earthed conductive part";
: u" w2 ]0 O& }& h– BASIC INSULATION but is not earthed, that is it has no second level of protection, it is termed a "basic-insulated
' M: |# J: E! vconductive part".* d! l! c) d: |+ Z
A circuit or conductive part is termed "earthed" if it is connected to a protective earthing terminal or contact in; @6 e7 g4 b2 G A5 H# P. k- x" p
such a way as to meet the requirements in 2.6 (although it will not necessarily be at earth potential). Otherwise& ^. z* G, S: o8 k
the circuit or conductive part is termed "unearthed". |
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