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引用第6楼wolfxu于2011-02-14 13:53发表的 :" ^# c* p% C9 M+ i9 z% A0 T0 Q) V
: F6 O# P$ d& P我一直搞不明白什么是直流电网电源。哪位可以帮忙解释一下? EN60950说得很清楚了。
! k# C% S4 L Y% s2 w2 W1.2.8.27 e, M* M& `- c+ a7 F
DC MAINS SUPPLY
% h7 \0 }* J2 b3 n9 ed.c. power distribution system, with or without batteries, external to the equipment, for. W6 o/ P! r: W9 y7 y8 R& D
supplying power to d.c. powered equipment, excluding the following:! z$ ]6 R$ G2 Z
− a d.c. supply providing power over TELECOMMUNICATION NETWORK wiring to remote! S. c9 t; M4 \. T1 @) P# o2 {7 F
equipment;
+ @* X1 V' O, b" F4 X' i− a limited power source (see 2.5) whose open circuit voltage is less than or equal to$ m0 t" U, `/ i: O1 ^; J# L. x1 J, ]
42,4 V d.c.;4 k9 H+ W; ]! W$ P6 X$ L4 k; \6 Y# \ D
− a d.c. supply whose open circuit voltage is greater than 42,4 V d.c. and less than or equal
5 ~3 A1 \/ [- j9 Mto 60 V d.c., and whose available power output is less than 240 VA
. r- n$ A* d2 w* ECircuitry connected to a DC MAINS SUPPLY is considered to be a SECONDARY CIRCUIT (for
0 v, c$ N: v) ]! ~) s2 pexample, an SELV CIRCUIT, a TNV CIRCUIT or a HAZARDOUS VOLTAGE SECONDARY CIRCUIT) in the' r5 e' z+ e. d
meaning of this standard.
1 _$ s4 r0 e' d6 V$ v) V. `NOTE See ITU-T Recommendation K.27 for bonding configurations and earthing inside a telecommunication
1 J- V6 s! j2 P; D' `building. |
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