Epson C 2900 Manual

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Confidential 3.9.2 Data Flow
Print data (electric signal) from the printer controller flows as shown below until it is turned into a print.
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3.10 Duplex
3.10.1 Major functions
- CLUTCH ASSY EXIT
Transmits the driving power from the DRIVE ASSY EXIT to Roll Assy Exit in the Fuser.
When the clutch operates, the Roll Assy Exit rotates in the reverse direction.
The clutch is stopped when the paper reached the Duplex.
- DRIVE ASSY DUP (PL11.2.5)
The DRIVE ASSY DUP supplies the driving power to the Lower Roll (ROLLER ASSY DUP) and 
Upper Roll (ROLL ASSY DUP1)....

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3.11 250 Paper Tray
3.11.1 Major functions 250 Paper Tray
- GUIDE SIDE ASSY R (PL12.5.8) / GUIDE SIDE L (PL12.5.6)
The GUIDE SIDE ASSY R and GUIDE SIDE L can move at a right angle to the paper transfer direc-
tion to align the paper width.
- END GUIDE
The END GUIDE can move in the paper transfer direction to determine the paper size.
- HOLDER ASSY RETARD (PL12.5)
The HOLDER ASSY RETARD and the FEED ROLLER pinch the...

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Confidential 3.11.2 Major functions (Paper Feeder)
- SENSOR PHOTO (No Paper Sensor:PL12.4.13)
Detects the presence/absence of paper in the paper tray based on the position of ACTUATOR NO 
PAPER (PL12.4.19). (No paper: Sensor beam is intercepted)
- SOLENOID FEED MSI (PL12.2.15)
Transmits the driving power from the MOTOR ASSY SUB (PL12.2.16) to ROLL ASSY FEED. (Refer 
to 6.6 MOTOR ASSY SUB)
- ROLL ASSY FEED (PL12.4.4)
When the...

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SENSOR PHOTO
(Tray2 No Paper Sensor)
SENSOR PHOTO
(Paper Path Sensor)TURN ROLL RUBBER
(ROLL ASSY  REGI)
TURN ROLL METAL
(ROLL REGI METAL) CLUTCH ASSY  DRVROLL ASSY  FEED
SOLENOID FEED MSI
MOTOR ASSY  SUB PWBA FEED H 

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4. Operation Modes
4.1 Operation Modes
For the operation of the printer, the following four modes are provided.
- READY mode
The printer is ready for printing.
- PRINTING mode
The printer is under printing.
- Sleep mode (Energy star)
The printer is under power saving.
- Deep sleep mode
The printer is under power saving. 

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5. Control
5.1 Control of Paper Size
The printer doesn’t have switches for detecting paper size, and only length of paper is detected by the 
Regi Sensor when feeding paper. If printing data and paper size don’t match, error is sent to the ESS.
5.2 ROS Light Quantity Control
The image data are entered to the laser diodes in the ROS as electric signals (data are expressed with 
high and low voltage values), and the...

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5.3 Process Control
For a stable printing, the parameters related to the image forming must be corrected as necessary. The 
control of the entire printing process including parameter correction control is called process control.
Mainly, the process control is performed in the following two methods, both of which are performed 
after every 25 cumulative prints upon termination of a print run or during a continuous...

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Confidential 5.3.2 Toner Density Control
The toner density must be kept constant to attain stable printing image. The control system for this pur-
pose is called toner density control.
1) PCDC (Pixel Count Dispense Control)
The quantity of the toner to be consumed in the developing process is calculated by counting the 
video signals entered to the ROS. The quantity of the toner to be consumed is calculated by the 
toner...

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5.4 Color Registration Control
The printer uses a tandem system where the drums and developers are arranged respectively for each 
of yellow, magenta, cyan, and black colors. Since the images are formed on the drum of each color to 
be overlaid one another, a color shift may occur. The color registration control calculates how much the 
registration is shifted, and adjusts the ROS write timing.
The lateral...