Epson Stylus Color 640 Service Manual page 146

EPSON Stylus Color 440/640/740
5.2.2.7 Head Voltage ID Input
Head voltage value adjustment function enables you to write printhead
ID. This operation is considered the most important to maintain proper
ink discharging system. If an ID is not written correctly, it results in white
or color lines and also gives bad influence on dot weight. This
adjustment is required in the following cases.
1. When exchanging the main board
2. When exchanging the printhead
3. When exchanging the printer mechanism
Before or after performing this operation, refer to the
table 5-2 and perform any appropriate adjustments or
operations.
1. When replacing any of the parts above, make a note of VH voltage
ID appointed in advance. You can find the VH voltage ID on the
following position:


Printhead: On the side face of the printhead.


Printer mechanism: On the label of the packing box of the
printer mechanism.
2. Apply the main menu (Figure 5-21). (See Section 5.2.2.2.)
3. By using the Up/Down arrow key, select Adjustment in the main
menu.
Chapter 5 Adjustment
4. By using the Up/Down arrow key, select Head Voltage ID Input in
the adjustment menu. (Figure 5-19.)
The following screen appears.
Figure 5-22. Head Voltage ID Check/Input Select Menu
5. By using Up/Down arrow key, select Change data, and the
following screen appears.
Figure 5-23. Head Voltage ID Input Menu
Revision A
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