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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)
7 R" c4 U+ x" D# tThe term "conductive part" refers to an electrically conductive part that is' m0 z8 {' K4 Z
– not normally energized, and
# w+ P. @, L$ J: }6 ]– not connected to any of the following:
$ ?! H& L; G3 `' Y+ l n7 v• a circuit at HAZARDOUS VOLTAGE, or
. M: A5 u# F8 {. P* z/ u6 e• an ELV CIRCUIT, or
! a$ K# Q3 l% \0 O% L- J/ q1 a• a TNV CIRCUIT, or% U, c0 T3 e5 Q, E& I
• an SELV CIRCUIT, or
: H6 y$ ]) }" a) |* m* a4 s• a LIMITED CURRENT CIRCUIT.
5 B" i8 v6 | ^, B h* _ o5 ^Examples of such a conductive part are the BODY of equipment, a transformer core, and in some cases a* u; r0 U- c9 u" a S3 z) P
conductive screen in a transformer.* C' d" Q6 \) E- k
If such a conductive part is protected from a part at HAZARDOUS VOLTAGE by:0 h- e8 W; M7 Y- e+ a! U
– DOUBLE INSULATION or REINFORCED INSULATION, it is termed a "double-insulated conductive part";
9 n: T P' B9 W! [# g– BASIC INSULATION plus protective earthing, it is termed an "earthed conductive part";9 K* ~ T8 r; U T) ]" _+ Q5 [5 Z
– BASIC INSULATION but is not earthed, that is it has no second level of protection, it is termed a "basic-insulated+ G. t( a( `& X1 Z4 ~
conductive part".
9 q( e* j! m: z% J* I5 MA circuit or conductive part is termed "earthed" if it is connected to a protective earthing terminal or contact in
( H/ Q5 J+ N) d3 ssuch a way as to meet the requirements in 2.6 (although it will not necessarily be at earth potential). Otherwise
6 X* r' m U/ ~: j) Z6 ^/ qthe circuit or conductive part is termed "unearthed". |
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