Hitachi IJ PH Service Manual page 193

6.6.4 Handling of the charge related faults
- The model PX, PXR and PH are changed from the model KX in terms of handling of
the charge related faults as follows.
Model KX
Faults Ink ejection
No electrical Ink is
charge stopped.
(No Ink Drop
Charge)
In sufficient Ink is stopped
electrical charge
(Ink Drop
Charge Too
Low)
Excessive Ink is stopped
electrical charge
(Ink Drop
Charge Too
High)
Model PX, PXR and PH
Faults Ink ejection
No Ink Drop Ink is stopped.
Charge
(Ink ejection is
kept in case of the
maintenance mode)
Ink Drop Ink is stopped
Charge Too Low
Ink Drop Ink ejection is
Charge Too kept.
High
Conditions that the fault occur
The APH waveform is checked, and the fault occurs when the
APH signal is not detected in a given time.
The ink stream bent is detected. The fault is detected in the
ready state only.
The APH waveform is checked, and the fault occurs when the
APH signal is lower than the threshold level in a given time.
The insufficient electrical charge caused by a fault of the ink
drop generation status, and the ink bent are detected. The
fault is detected in the ready state only.
The APH waveform is detected, and the fault occurs when APH
signal exceed the judgment value in a given time.
The leakage noise and external noise are detected in the ready
state. The fault is detected in the ready state only.
Conditions that the fault occur
The APH waveform is checked, and the fault occurs when the
APH signal is not detected in a given time.
The ink stream bent is detected.
The fault is detected in the standby state also.
Ink ejection is kept when the IJP is the service maintenance
mode to clear the cause of the trouble.
(The fault occurs when ink is not charged even when the ink
is ejected. In this case, it should be clarified whether the ink
drop generation status is wrong or charge voltage is not
output while ink ejection is kept.)
The APH waveform is checked, and the fault occurs when the
APH signal is lower than the threshold level in a given time.
The insufficient electrical charge caused by a fault of the ink
drop generation status, and the ink bent are detected. The
fault is detected in the ready state only.
The APH waveform is detected, and the fault occurs when
APH signal exceed the judgment value in a given time.
The leakage noise and external noise are detected in the
ready state. The fault is detected in the ready state only.
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