Epson DFX-8500 Service Manual page 68

Cooling fan:
The C204 PSB/PSE board includes a cooling fan that is driven by +37 VDC. The fan lowers the temperature
of the PSB/PSE board circuit components and the carriage motor.
Voltage
+37 V (Voltage Point 1 - Ground
Point 1)
+37 V (VP2-GP2)
+37 V (VP3-GP3)
+5 V – GL
VX - GL


Protection circuits:
These +37 VDC line blocks perform voltage control. They limit current, and prevent voltage from becoming
too high.


Control and status signals:
The PSB/PSE board receives two control signals from the C204 main board and outputs two status signals
to the main board. See Table 2-4 for the meaning of each signal.


Fatal error recovery:
When the printer detects a fatal error, the PSB/PSE board is shut down for approximately 10 minutes by the
DRERR signal. You must wait 10 minutes before turning the power on again.
Table 2-3. PSB/PSE Board Output DC Voltages
Board
C204 DRV-B
C204 Main
C204 DRV
C204 PSB/PSE
C204 Main
C204 DRV
C204 DRV-B
C204 PNL
C204 Main
C204 DRV
C204 DRV-B
Application


Printhead driver circuit #1


Printhead driver circuit #2


Carriage motor


Paper feed motor


Platen gap motor


Ribbon feed motor


Head fan


Carriage fan


Plunger


Optional cutter motor


Cooling fan on the PSB/PSE unit


All logic systems operating voltage


Paper feed motor hold voltage


Plunger hold voltage


Platen gap motor hold voltage


Power for all the sensors


Voltage for power system pull-up. It is
switched by VXCNT signal of the CPU (IC2).
OPERATING PRINCIPLES
2-15