Azbil MagneW Two-wire PLUS+ MTG15A, User Manual

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Electrode status diagnostic troubleshooting
Troubleshooting
If a problem occurs during electrode status diagnostic, take appropriate actions in accordance
with the following procedure.
Trouble Check point and troubleshooting
„
Electrode status diagnostic
mistake when fluid is filled
because the unit is used in the
place where the flow rate
changes swiftly.
When the flow rate swiftly changes due to pulsations
from the pump, the function may recognize some of the
swinging flow rate signals as those in the empty status or
scale on electrode and mistakenly determine it as empty
or scale on electrode. In this case, it is recommended to
install the unit in the place where no effects from the
pulsation can be reached, e.g., by securing a longer
upstream straight pipe section. When the unit is installed
in a place where swift change of the flow rate may cause
misdetection of the empty or scale on electrode status
when fluid is filled, set this function to OFF. Please note
that increasing the damping time constant does not solve
this problem because this function determines the empty
or scale on electrode status based on the signals before
the damping process.
„
Empty not detected when the
pipe is empty.
If there is conductivity between electrodes or between
the electrode and grounding ring due to the fluid left in
the pipe, etc., the empty status may not be detected even
when the pipe is empty. In this case, this function is not
available. Set it to OFF.
If the display and output are not always fixed to zero
because, for example, the fluid drops on the electrode,
they may become stable at zero by increasing the setting
value for low flow cutoff and setting the auto spike cut to
ON.
„
Electrode status diagnostic
operation error after the
surrounding noise
environment has been changed
by expansion of equipment etc.,
such as changing the
installation location or
installing the high-current
motors or pumps.
Since change of the environment also changes the noise
volume, the electrode status diagnostic may not function
correctly with the conventional threshold value for it. In
this case, reset the threshold value.
„
Empty detected with flowing
fluid in fluid-filled status
(empty not detected with
stationary fluid).
The empty status may be detected even when the fluid is
filled because of the effects of the flow noises generated
from the flowing fluid. In this case, reset the threshold
value so that the empty status is not mistakenly detected
when the fluid is flowing.