4-2
Chapter 4. TROUBLESHOOTING
No. Type
Description
Likely cause
Corrective action
Automatic
recovery
1
Wn Empty (flow path not full) The flow path of this device has
not been full for some time.
Fill the flow path with the fluid.
✓
Inf Flow rate measurement
error
A flow rate measurement error
occurred due to a cause such as
bubbles in the flow path of the
device.
Check for problems in the
installation environment or
instrumentation.
2
Wn Accuracy-guaranteed
flow rate exceeded
Fluid is flowing at a rate greater
than the rated (accuracy-
guaranteed) flow rate.
Use this device within the rated
flow rate range.
✓
3
Wn Analog output range
exceeded
The rated flow rate was exceeded,
or an analog output correction
parameter value is invalid.
Use this device within the rated
flow rate range.
Set a valid parameter value.
✓
4
Wn Parameter error
(1) Checksum error
(2) Number of write
cycles exceeded
(1) A checksum error occurred
during parameter data reading
or writing.
(2) Parameters were written more
than the specified number of
times.
(1) Write parameters again.
(2) Replace the product.
–
5
Wn Watchdog time-out
A reset by a communication
command, or malfunction due to
electrical noise, etc.
If the warning persists after
turning the power off and back
on, request repair.
–
6
Al
Flow path or circuit
temperature out of range
The sensor unit has failed.
•
Check that the fluid
temperature and the
ambient temperature meet
the specified operating
conditions.
•
If the alarm persists after
turning the power off and
back on, request repair.
–
Wn
The fluid temperature or the
ambient temperature does not
meet the specified operating
conditions.
7
Al
Measurable flow rate
exceeded
The flow rate is greater than 115
% of the measurable range.
Use this device within the rated
flow rate range.
✓
8
Al
Totalizer pulse output
error (flow over range)
When totalizer pulse was being
output, the flow rate exceeded
the rated measurable range for a
certain period of time.
Use this device within the rated
flow rate range.
✓
Wn
When totalizer pulse was being
output, the flow rate far exceeded
the rated measurable range for a
certain period of time.
9
–
(Not used)
–
–
–
10
Al
Heater control error
The heater, temperature sensor,
or electric circuit has failed, so the
heater cannot be controlled.
If the alarm persists after turning
the power off and back on,
request repair.
✓
11
Er
Parameter error
A type of parameter not
supported by this device, or
an illegal parameter value, was
downloaded by the loader.
If the error, alarm, or information
persists after changing the
parameter and turning the
power off and back on, request
repair.
–
Al
Parameter mismatch
Parameter values are abnormal,
etc.
Inf Out-of-range parameter
Parameter values are out of range.
