Hitachi UX Twin Nozzle, Service Manual

Page: 98 / 355

3-22
3.3.6 EZJ134 board (Nozzle2 drive board)
[Function]
-
Control of nozzle (charging voltage control, excitation voltage, APH detection etc.) is
performed.
[Setting of switch/check point/LED display etc.]
- Setting of switch
SW1
Set both bits upward.
- Check point/ LED
Reference
number
Name Contents
TP4 GND Ground
TP3
Charging
signal Character signal which charged ink drops
TP1
Excitation
signal Sine wave signal applied to a nozzle
[Note for EZJ134 board replacement]
- When replacing boards, be sure to turn OFF the main power switch.
- Set up SW1 according to the nozzle diameter.
- After replacing the board, confirm the charging voltage.
- Perform the Excitation adjustment and Auto-phase gain adjustment.
- When removing the connector of CN1 and CN3, hold the socket housing and
pull them out in straight.
[Replacement procedures of EZJ134 board]
(1) Turn off the power.
(2) Remove the protective cover.
*) As the drawing below, push the hook of fixing spacer with finger and pull up the
protective cover. (Three spacers)
(3) Remove the connectors from CN2 and CN4.
Connector on board
Hold the socket housing
Mark
Protective cover
Spacer for fixing
the protective cover
Push the hook
Pull up
the cover
Metal plate for spacer fixing for protective cover
(2 on top and 1 at the bottom) of CN2 and CN4.
With respect to the
excitation adjustment,
refer to “2.3.1 Excitation
adjustment”.
With respect to the
excitation adjustment,
refer to “2.3.1 Excitation
adjustment”.
With respect to the auto
phase gain adjustment,
refer to “2.3.4 Auto phase
gain adjustment
”.
Metal plate for spacer fixing for protective cover
(2 on top and 1 at the bottom) of CN2 and CN4.