Power Supply Board Summary - Epson Stylus PRO 7500 Service Manual

EPSON Stylus Pro 7500

2.4 Power Supply Board Summary

Depending on the printer model, either 100V AC or 220V AC is supplied to the printer
when the printer is plugged into an liveoutlet.
The power switch consists of a secondary power switch system. A secondary power switch
system is a system where the power supply board operates with a minuscule power level as
long as the power cable is connected, even when the power switch is turned off.
NOTE: The power supply board is configured so that it does not stop
immediately even after the power switch is turned Off, but after the ink
system's end sequence has been performed, the power goes Off.
Therefore, the printer should not be operated by turning a power supply
tap switch On and Off.
The power supply board is equipped with an overcurrent protection fuse for protecting it
against overcurrent. The fuse rating is shown in the following table.
Table 2-5. Fuse Rating
Input Voltage Range [V AC]
100V AC ± 10%
The C299MAIN board has three control signals, described in detail in the table below.
Operating Principles
Fuse Rating
125V AC/6.3A
Power Supply Board Summary
Table 2-6. PS Board Signal Summary
Signal Name Condition
During operation
+28V/+42V
REM_ON
(MAIN ->PS)
Printer off
During operation
(= H)
AC_OFF
(MAIN<-PS)
Printer off
(= L)
Turning on
POWER_SW
(Panel/MAIN -> PS)
Turning off
Revision A
Function
On and Off is controlled by the C299MAIN
board.
• If this terminal is shorted, the drive system
power supply, 28 V DC and 42 V DC, becomes
active.
• If this terminal is cleared (= L), the drive
system power supply, 28 V DC and 42 V DC,
becomes 0 V DC.
• The 5 V DC power supply is not controlled by
this terminal.
The power switch goes On, the power supply
board unit starts and each output becomes
active. Afterward, the "H" signal is sent to the
C299MAIN board.
The power switch goes Off, and the each output
of the power supply board unit becomes
inactive, or if the input voltage drops below the
rated voltage value, the "L" signal is sent to the
C299MAIN board.
This is connected to the panel unit's power
switch.
• When the switch is in the On state, this
terminal is shorted. the power supply board
changes to the operating state.
• When the switch is in the Off state, this
terminal is cleared. After waiting in the
operating state for 10 plus seconds and up to
several minutes, the power supply unit goes off.
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