Epson GT-1200, Руководство по обслуживанию

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ADF Adjustment
Rev. A
5-8
5.1.3.1 Sensor Adjustment
This ADF is internally equipped with the following 3 photo-interrupter
sensors; empty sensor, registration sensor, and reverse sensor.
Since these sensors function by transmitting infrared ray, paper debris
and dust built up around the sensors bring change in the voltage level of
the signals returned to the CPU, and paper is not detected correctly as a
result. Generally, photo-interrupter sensors are inevitably produced with
uneven sensitivities. Therefore, the amount of light emitted from the LED
must be controlled by the ADF side. This ADF increases LED emission
when the voltage level of the signal sent to the CPU drops blow specified
level. For this reason, it is essential to provide periodical cleaning to the
specified parts as well as to write the highest voltage level, which is
electrically unique to each sensor, into the EEPROM under paper empty
condition after any of the photo-interrupter sensors is replaced. Without
this operation, the ADF continues to refer to the value stored before
replacement, and the following may occur as the result:
q
Document is not fed.
q
Document jams near the entrance on the transporting belt.
q
Document jams in the reverse mechanism.
1. Set the ADF to the scanner.
2. Open the switch cover on the ADF and remove 1 screw securing the
rotary switch cover, then remove the rotary cover.
3. Set the Dip-switches as shown below.
1 2 3 4 5
O N
O F F
4. Open and then close either the paper eject cover or the paper feed
cover. (The sensor adjustment mode is set with this motion.)
5. Press the push button directly attached to the control board, and the
automatic sensor adjustment program starts running to make
adjustment and setting for each sensor.
While the program is running, the LED (red) on the control board lights up,
and goes off when the adjustment is properly carried out. If the LED
indicates an error status as shown in the table below, take any necessary
actions.
Table 5-4. LED Status
LED indication Corresponding condition
OFF The adjustment is properly executed.
ON
EEPROM initialization has failed.
(Refer to Section 4.1.2.2.)
Blinks (Interval: 1000 ms) Registration sensor is defective.
Blinks (Interval: 500 ms) Timing sensor is defective.
Blinks (Interval: 50 ms) Reverse sensor is defective.
CAUTION The factory setting for the Dip-switches are all
OFF. Therefore, set all the switches back to Off
after adjustment.