Adjustment The Paper Sensors - Epson Stylus PRO 7500 Service Manual

EPSON Stylus Pro 7500
Table 5-6. "Sensor" Function Confirmation Items
Display Item
CR Home Position Shows the state detected by the CR_HP sensor.
PF Home Position Not used.
Cover Shows the front cover open / closed state.
Lever Shows the paper set lever's state (Forward: Down Back: Locked).
Paper Edge AD / Paper
Shows the state detected by the paper sensors' (P_EDGE,
Front AD / Paper Rear
P_FRONT, P_REAR).
AD" *1
Paper Thickness Shows the state detected by the paper thickness detection sensor.
Shows the state detected by the PG cam home position detection
Head Slide
sensor.
Shows the temperature detected by the Thermistor inside the B and C
Temperature B / C
heads.
Ink Lever B / C Not used.
[ ] [ ] Ink ID Not used.
Shows the state detected by the I/C sensor, whether the I/C is present
B C Ink NOT [ ] [ ] [ ] or not, and displays the name of the I/C that is not installed.
(Example: When the Lm I/C is not installed, "Lm" is displayed.)
Shows the state detected by the ink low detection sensor and shows
B / C Ink END [ ] [ ] [ ] the name of the I/C where the ink low state is detected. (Example:
When the ink is low in the Lm I/C, "Lm" is displayed.)
*1 This should definitely be done after a new C299MAIN board has been installed.
You need to perform the "Adjustment the Paper Sensors" as
described on the next page after replacing the Main board as well as
any of the P_THICK, P_REAR, and P_FRONT sensors.
Adjustment
Contents
Adjustment Steps

ADJUSTMENT THE PAPER SENSORS

The P_EDGE, P_REAR and P_FRONT sensors which detect the paper are reflective type
optical sensors, so if the sensors themselves and the main board are replaced, the following
adjustment should be made to set the sensors' detection level to the proper value.
n
For the reasons given on the preceding page, depending on the
base unit's serial code and the firmware version, the adjustment
methods for the P_FRONT / REAR / EDGE sensors differ, so the
appropriate adjustment should be made.
n
If the same sensor adjustment as that for a Type 2 unit is
performed for a Type 1 unit, the sensor's sensitivity will rise too
high and it will be easy for it to be influence by stray light, and it
may no longer be impossible for it to correctly detect EPSON
genuine paper.
n
If you are turning the VR element (volume resistor) on the main
board to make adjustments, care should be taken not to touch the
other elements on the board or the frame, etc.
n
It is easy for each sensor to be influenced by stray light from the
sun or from the room lighting, etc. The P-FRONT sensor in
particular is easily influenced by stray light, so printing should
always be done with the printer covers securely in place.
n
If the specified paper is set in the printer for each sensor
adjustment, the paper set lever should be moved to the paper set
position securely so as to stabilize the paper over the sensors.
n
The papers used for this adjustment (PPC, Kimoto Tracing
Paper #300) should be replaced periodically. If there is any dirt
(ink, foreign matter adhering), damage (wrinkles, tearing) in the
standard paper, an accurate adjustment cannot be made, so the
standard paper should be replaced after adjustment of about 20
printer units.
Revision A
184