1.7. POWER DISTRIBUTION
The PSU su24V, +5V, -5V, and +12V to the machine through the
MBU.
The ac switching circuit on the PSU generates one +24V supply. This supply
also goes to the interlock switches. If the ADF exposure cover interlock
switch is closed, the +24V SDU supply is generated, and this is supplied to
the SDU board. If the platen cover interlock switch is closed, the +24V ADU
supply is generated, and this is supplied to the ADU board.
The SCU board pr5V terminator power to the SCSI connector.
There are four LEDs on the MBU (one on each power line) to indicate the
condition of each power supply.
Read SN
ADP
Scanner Indicator
Panel
Home Position SN
Feed out
SN
Cooling Fan Motor
AC Switching
Circuit
ADF Exp. Cover
Interlock SW
Platen Cover
Interlock SW
+5V
+5V
+5V
+12V
+5V
- 5V
+24V
+12V
+24V SDU
+24V ADU
+5V
-5V
+12V
+24V
+5V
-5V
+12V
+24V
+5V
Document Table
Position SN
Document SN
Feed
SN
+5V
+5V
+5V
+5V
+24V ADU
Document Table
Lift CL.
Pick-up CL.
Paper Feed
Motor
Paper Transport
Motor
+24V
ADU
+24V
ADU
+24V
ADU
+24V
ADU
+5V
+24V SDU
+24V SDU
+24V SDU
+5V
Scanner Motor
Xenon Lamp
+5V
+5V
PSU
MBU
SCU
SIMM
IEU
SDU
ADU
+5V
+5V
+5V
SBU
AC Power
Main SW
LED 2
LED 4
LED 3
LED 1
DCU, VIU
-5V
SCSI
+5V
G404V500.wmf
Over
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In
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October 9th, 1995
OVERALL MACHINE INFORMATION
POWER DISTRIBUTION
1-13