NEC SV8500, Manual

Page: 2824 / 3438

VOL.3-337
CHAPTER 2 TERMINAL-RELATED DEVICES
8.5.6 PA-PW54-B (DPWR)
General Function
The PA-PW54-B (DPWR) circuit card supplies operating power to circuit cards accommodated in the PIM. The
-48V input power source, which is converted to +5V, -5V, and +12V, is distributed to each circuit card in the
PIM. This card is also equipped with a Ringing Generator Unit (RGU), whose output frequency and voltage can
be selected among 20Hz, 25Hz, 75Vrms, 90Vrms by key setting on this card. In addition, a Howler Tone circuit
resides on this card.
Location of PA-PW54-B (DPWR) card within the System
+5V, +12V, -5V
CR (For LC)
HOW (For LC)
-48 V (For LC, TRK)
-48 V
NFB NFB
REL REL
PA-PW54-B (DPWR)
DC-DC
RGU
HOW
SUB
PWR
PA-PW55-B (PWR)
DC-DC
RGU
HOW
SUB
PWR
+80 V (For MWL)
+80V (Option)
Note
Note:
The +80V input is required for activating Message Waiting Lamps (MWLs).