Thermal Head Voltage Adjustment - Ricoh C211 Service Manual

2. THERMAL HEAD VOLTAGE ADJUSTMENT

Purpose: To maintain master making quality and extend the lifetime of the
thermal head.
NOTE: This adjustment is always required when ever the thermal head
or the power supply board is replaced.
[B]
1. Remove the rear cover and the right cover and right cover of the
machine.
2. Disconnect the connector [A] from the plotter unit.
3. Check the voltage noted on the decal, located on the thermal head.
(The voltage will vary with each thermal head.)
4. Access "I/ Check Mode".
•
Turn on the main switch while holding the Print Start, Stop and
Clear keys.
5. Input 35 in the copy counter using the number keys, and set "0" in the
Memory/Class display by pressing the Memory/Class key.
6. Press the Print Start key to apply the thermal head voltage.
7. Confirm that the voltage between one of the VHD terminals and one of
the ground terminals of CN503 is at the level specified on the decal
(Within + 0 V ,– 0.1 V).
8. If it is not correct, adjust VR3 on the power supply board.
NOTE: Press the stop key to stop applying the thermal head voltage.
Do not keep the thermal head voltage on for a long period
(longer than several seconds).
SM
[A]
5-7 C224