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引用第6楼wolfxu于2011-02-14 13:53发表的 :
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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。8 j [) _/ Z' X' r+ { T: D/ e
1.2.8.2. ~& @9 a. I# {/ d" ~3 p% V
DC MAINS SUPPLY2 W3 Q/ q/ h# X0 C5 d6 S( k
d.c. power distribution system, with or without batteries, external to the equipment, for/ X7 F' n$ [3 h0 W" }7 v
supplying power to d.c. powered equipment, excluding the following:
' q4 ]2 q- a# M( s" J9 W3 S/ F) V− a d.c. supply providing power over TELECOMMUNICATION NETWORK wiring to remote' X3 s! F. \) |2 U0 Y, _& y8 n, K. i
equipment;
I2 ?% t( f7 y1 U R− a limited power source (see 2.5) whose open circuit voltage is less than or equal to
! a* s) z! M Z# L7 T; X; e* S42,4 V d.c.;1 y$ ~. E& S$ D- D0 N
− a d.c. supply whose open circuit voltage is greater than 42,4 V d.c. and less than or equal
: r- ], r9 D5 tto 60 V d.c., and whose available power output is less than 240 VA/ B; @3 I- I j8 M2 ^
Circuitry connected to a DC MAINS SUPPLY is considered to be a SECONDARY CIRCUIT (for+ x/ f |# m9 _( r4 q
example, an SELV CIRCUIT, a TNV CIRCUIT or a HAZARDOUS VOLTAGE SECONDARY CIRCUIT) in the' k0 B8 U( N. V# t2 a) ]6 Q) z
meaning of this standard.
$ @5 L5 q7 {, m% S8 fNOTE See ITU-T Recommendation K.27 for bonding configurations and earthing inside a telecommunication
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