- 14 -
Maintenance and Troubleshooting
Maintenance
To ensure proper operation, conduct periodic inspection at least
once a year.
If the self-diagnostic function displays an alarm that does not
clear even though the cause of the alarm is eliminated, request
servicing from Koganei. Contact the Overseas Department for
more information.
The addresses and telephone numbers are shown at the back of
this manual.
Troubleshooting
● Abnormalities and remedies
Symptom
Remedy
Nothing appears on the
display.
・
Make sure the supply power voltage and polarity are being
applied correctly.
・
Make sure that connectors are connected correctly.
The flow rate display
does not become zero
even when valves
upstream or down-
stream from the flow
meter is closed and
there is no flow. (Output
signal is not 4 mA. )
・
Make sure there are no air leaks in the piping.
・
Make sure that wiring is correct.
・
When the flow meter is installed on horizontal piping with the
display sideways, influence of the installation attitude may cause
zero point drift. (Since installation on horizontal piping with the
display sideways causes the accuracy guarantee flow rate range
to become 5 to 100% FS, set the low flow cut in this case to 5%. )
・
In a location subject to large ambient temperature fluctuation and
large flow fluid temperature fluctuation, convection within the
piping may be detected as flow. Perform measurement after
temperature has stabilized sufficiently.
Large instrument error
compared against the
standard instrument.
The instrument is
outside the accuracy
range.
・
Make sure there are no air leaks in the piping.
・
Check for foreign matter trapped in the main channel orifice. If
foreign matter is present, remove it.
・
Check for dirt, oil, or other foreign matter in piping and the flow
meter connection port. If foreign matter is present, Koganei
servicing and replacement are required. Contact your nearest
Koganei sales office or the Overseas Department.
・
Check to make sure that wiring is correct.
・
Check to make sure that there is no large fluctuation in flow rate
within a few seconds and that the measurement range is not
exceeded by a large amount.
● Alarm displays and required actions
Alarm
Code
Item
Description
Cause
Remedy
Flow rate over
A flow rate that
exceeds the value
set by the maximum
display value
parameter setting is
flowing. Or a back
flow that exceeds
the back flow rate
range is flowing.
There may be
a high flow
rate outside of
the maximum
display range
or back flow.
Note 1
Check if a high flow rate exists
and eliminate its cause. If the
instantaneous flow rate display
when the alarm occurs shows
a minus (–) sign, back flow
occurs. Eliminate the cause of
the back flow. The alarm will
cease displaying when the
actual flow rate becomes within
the display range flow rate.
Registration
data abnormal-
ity 1
Abnormal channel
ID numbers
registered. Correct
flow rate calculation
cannot be
performed.
The registered
channel ID
numbers may
be wrong.
Use maintenance mode to
register the correct channel ID
numbers.
Note 2
If changing the
setting does not clear the
alarm, turn the instrument off
and then back on again. If this
does not clear the alarm,
request servicing.
Registration
data abnormal-
ity 2
Correct calculation
cannot be
performed because
of abnormal data
registered for the
flow sensor
characteristic
values.
Registered
characteristic
data may be
corrupted,
resulting in
abnormal
values.
Turn the instrument off and
then back on again. If this
does not clear the alarm,
request servicing.
Sensor
abnormality 1
Flow rate signal
is outside the
proper range.
The signal level
may be exceedingly
low due to a short
circuit caused by
adherence of
foreign matter or
excessive back flow
that exceeds the
measurement
range.
If excessive back flow is
the cause, this error will
clear automatically when
the flow rate returns within
the measurement range. If
it is not due to excessive
back flow and the alarm
does not clear after a
number of hours, request
servicing.
Sensor
abnormality 2 Flow rate signal
level may not
match the actual
flow rate.
Sensor may be
malfunctioning or
output may be
dropping. Foreign
matter may be
adhering to sensor,
or there may be
condensation on
the sensor, etc.
Pass dry air through the
system. If the error does
not clear after a number of
hours, request servicing.
Sensor
abnormality 3
Sensor
abnormality 4
Heater voltage is
outside the
proper range.
The sensor may be
damaged, or there
may be a short
circuit due to the
adherence of
foreign matter, etc.
If the error does not clear after
a number of hours, request
servicing.
Memory abnormality
Instrument
information
data
abnormality
Sum mismatch
when accessing
EEPROM.
Data may
have been
corrupted by
noise, etc.
Turn the instrument off and
then back on again. If this
does not clear the alarm,
request servicing.
Characteristic
value information
data abnormality
Setting
information
data
abnormality
Power was cut
off during data
writing, which
created the
risk of
abnormal
completion.
Reconfigure the data, and
then turn the instrument off
and then back on again. If
this does not eliminate the
alarm, request servicing.
Integrated
information
data
abnormality
Perform an integrated value
reset, and then turn the
instrument off and then back
on again. If this does not
eliminate the alarm, request
servicing.
Note 1: If parameter setting were used to change the maximum display value,
this alarm occurs in accordance with the changed setting.
2: For information about channel ID numbers, see "Bypass Unit
Replacement Guidelines" on page 15.
