Hitachi IJ PH - Page 77

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3.3.2 EZJ106 board (NH board)
[Function]
- Control of nozzle (charging voltage control, excitation voltage, APH detection, PTC
control and the like) is performed.
[Setting of switch/check point/LED display and the like]
- Setting of switch
Nozzle size
６５μm
ＤＳＷ１
ＤＳＷ2
- Check point/LED
Reference
number
Name Content
TP1 APH signal Charged amount detection signal of ink drops
TP3 GND Ground (for APH)
TP12 Charging
signal
Character signal charging ink drops
TP13 GND Ground (for charge/excitation)
TP14 Excitation
signal
Sine wave signal applied to a nozzle
TP15 PTC signal PTC drive signal
LED1 APH signal For APH signal check with eyes
[Note at the replacement]
- When replacing boards, be sure to turn off the power.
- Set up DSW1 and DSW2 according to the nozzle diameter.
- After replacing the board, confirm the charging voltage.
- Perform the excitation adjustment.
- Perform the auto phase gain adjustment.
[EZJ106 board external views]
With respect to the
charging voltage
confirmation, refer to
“2.3.2 Charging voltage
confirmation”.
With respect to the auto
phase gain adjustment,
refer to “2.3.4 Auto phase
gain adjustment”.
The EZJ106 board has a portion where high voltage is applied. When performing
the adjustment in a state where the Electric Component cover is opened, be fully
careful about an electric shock.
Caution against an electric shock
With respect to the
excitation adjustment,
refer to “2.3.1 Excitation
adjustment”.
Three setscrews
Protective
cover
TP14: Excitation signal
TP13: Ground
TP12: Charging signal
TP3: Ground
TP1: APH signal
TP15: PTC signal
DSW1
Three setscrews
Two studs for fixing
a protective cover
Three setscrews
Two studs for fixing a
protective cover
(Marked side）
LED1
DSW2
(Marked side）
Mark
Mark