Azbil MPC0002 User Manual

6-1
Chapter 6. TROUBLESHOOTING
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Alarm code display
When a flowrate deviation alarm occurs or when an alarm occurs during controller
self-diagnostics, the operating mode currently selected at "Operation selection at
alarm occurrence" C- 16 in the function setup is forcibly switched to. (Except AL7 1)
The upper display alternately indicates the alarm codes shown in the table below
and the regular display.
Alarm code Error Cause Countermeasure
AL0 1
Flowrate deviation lower
limit alarm
Insufficient alarm judgment delay time,
insufficient power voltage, insufficient
inlet pressure, excessive operating
temperature, etc.
Request for repair service if there is
no problem on the items listed on
the left.
AL02
Flowrate deviation upper
limit alarm
Insufficient alarm judgment delay time,
valve trouble, sensor trouble, etc.
Request for repair service if there is
no problem with the delay time.
AL7 1
Valve overheat prevention
limit is operated
During the control or fully-open mode,
the gas is forcibly shut-off by external
device.
When the gas is continuously shut
off by external device, set the set
flowrate to zero or valve fully-closed
mode.
AL8 1
Sensor error Sensor trouble, foreign object attached
to sensor, or entering of hydrogen or
helium gas.
If sensor is not restored after turning
the power OFF, then request for
repair service.
AL9 1
I/O correction data error Data corrupted due to electrical noise. Request for repair service.
AL92
Sensor calibration data error Data corrupted due to electrical noise. Request for repair service.
AL93
User setup data error Power shutoff during writing of data. Set data again.
Handling Precautions
• The alarm code is displayed only during the instantaneous flowrate, operating
mode and integrated flowrate are displayed.
• The timing for activation of the valve overheating limit (AL71) varies
depending on the model. As long as the conditions causing AL71 remain, the
current to the valve will be forcibly limited regardless of the setting for C-16
in the function setup. If this situation continues, the final result will be that the
valve is fully closed.
• If AL8 1(sensor error) occurs, the flowrate value will become indefinite.
Therefore, the control flowrate becomes indefinite even if "0: Control
continued (alarm ignored)" is selected at C- 16 in the function setup.
• When "1: Move to fully closed" or "2: Move to fully open" is selected at C- 16
in the function setup, the alarm display and the operating mode at alarm
occurrence can be maintained even after the cause of alarm is removed.
When canceling the alarm, make the alarm reset operation.
z
Canceling the alarm
Keep the [ENT] key pressed while the instantaneous flowrate is displayed.
The alarm can be cancelled after 3 seconds.

Azbil MPC0002 Specifications

General

Brand	Azbil
Model	MPC0002
Category	Controller
Language	English