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EPSON Stylus Pro 7400/7800/9400/9800
Revision B
Operating Principles
Print Mechanism Components
162
The sensors used in the paper feeding mechanism are explained below.
P REAR sensor
This is a photo-reflective sensor located on the backside of the H Top Cover. It
detects paper absence by detecting the rear edge of the paper, and detects the
leading edge of paper when the paper is loaded to let the printer start the paper
setting operation such as attracting the paper to the paper guides.
Paper set lever, paper thickness detection (P THICK1, P THICK2)
P THICK1 Sensor: A transmissive photosensor located on the right side.
P THICK2 Sensor: A transmissive photosensor located on the left side.
In the paper feeding mechanism, there is a point where paper thickness threshold is
set to 0.3 to 0.4 mm (P THICK2 sensor) and a point where that is set to 0.6 to 0.7
mm (P THICK1 sensor). When the Paper Set Lever is set on those points, the two
sensors start to operate.
The paper thickness detection range for moving the Paper Set Lever is 0.34 to 2.05
mm (design value). By a combination of the two sensors, the printer can determine
to reduce the pressure of the Paper Set Lever according to the paper thickness.
“Thick paper state” occurs when the connections are open.
There is no error processing since this mechanism can not determine whether it
has broke down or not.
Since the mechanism is always in recognition of thick paper, printing on thin paper
is carry out with the platen gap kept large.
Figure 2-13. Paper Feed Assembly (P Rear Sensor)
Table 2-5. Modes
Paper Thickness
Shield Plate
Sensor Output
P THICK2
P THICK1
P THICK2
P THICK1
Below 0.3 mm
Absent (Open)
Absent (Open)
L
L
0.4mm to 0.6mm
Present (Closed)
Absent (Open)
H
L
0.7mm to 2.0mm
Present (Closed)
Present (Closed)
H
H
Pressure release (Hi-Up)
Absent (Open)
Present (Closed)
L
H
Connector not connected
---
---
H
H
P Rear Sensor
Summary of Contents for Stylus Pro 7400
Page 1: ...EPSONStylusPro7400 7800 9400 9800 Large Format Color Inkjet Printer SERVICE MANUAL SEIJ05002 ...
Page 10: ...C H A P T E R 1 PRODUCTDESCRIPTION ...
Page 147: ...C H A P T E R 2 OPERATINGPRINCIPLES ...
Page 170: ...C H A P T E R 3 TROUBLESHOOTING ...
Page 207: ...C H A P T E R 4 DISASSEMBLY ASSEMBLY ...
Page 292: ...C H A P T E R 5 ADJUSTMENT ...
Page 373: ...C H A P T E R 6 MAINTENANCE ...
Page 380: ...C H A P T E R 7 APPENDIX ...
Page 385: ...Model PX 7500 7500S 9500 9500S Board C594 Main Sheet 1 of 4 Revison G ...
Page 386: ...Model PX 7500 7500S 9500 9500S Board C594 Main Sheet 2 of 4 Revison F ...
Page 387: ...Model PX 7500 7500S 9500 9500S Board C594 Main Sheet 3 of 4 Revison F ...
Page 388: ...Model PX 7500 7500S 9500 9500S Board C594 Main Sheet 4 of 4 Revison E ...
Page 389: ...Model PX 7500 7500S 9500 9500S Board C594 SUB Sheet 1 Revison C ...
Page 390: ...Model PX 7500 7500S 9500 9500S Board C594 SUB B Sheet 1 Revison E ...
Page 391: ...Model PX 7500 7500S 9500 9500S Board C594 SUB C Sheet 1 Revison D ...
Page 392: ...Model PX 7500 7500S 9500 9500S Board C594 PNL Sheet 1 Revison D ...
Page 396: ...PX 7500 7500S E PS ON S TYLUS PR O 7400 7800 No 03 R ev 01 C594 E LE C 011 202 201 200 ...
Page 397: ...PX 7500 7500S E PS ON S TYLUS PR O 7400 7800 No 04 R ev 01 C594 E LE C 021 203 204 ...
Page 398: ...PX 7500 7500S E PS ON S TYLUS PR O 7400 7800 No 05 R ev 01 C594 POWE 011 300 301 302 ...
Page 403: ...PX 7500 7500S E PS ON S TYLUS PR O 7400 7800 No 10 R ev 01 C594 ME CH 051 700 701 X15 700 ...
Page 410: ...R ev 01 C595 E LE C 011 200 201 202 PX 9500 9500S E PS ON S TYLUS PR O 9400 9800 No 03 ...
Page 411: ...PX 9500 9500S E PS ON S TYLUS PR O 9400 9800 No 04 R ev 01 C595 E LE C 021 204 203 ...
Page 412: ...PX 9500 9500S E PS ON S TYLUS PR O 9400 9800 No 05 R ev 01 C595 POWE 011 300 302 301 ...
Page 417: ...PX 9500 9500S E PS ON S TYLUS PR O 9400 9800 No 10 R ev 01 C594 ME CH 051 701 X15 700 700 ...