Troubleshooting
47
Troubleshooting
Troubles with measurement
Symptom
Possible cause
Remedial action
Fluctuation in
measured value
Non-uniformity of samples
z
Pull up the detector, and check variations with
air. (There are no variations under normal
conditions.)
z
Attach an operational check board, and check
variations. (There are no variations under
normal conditions.)
z
Select a location where sample can be stirred
properly. Set up the detector there.
The impact of air bubbles caused by aeration
is large.
Set up the detector in a location that will prevent
aeration-caused air bubbles.
The sample’s particle size is large and
subsides easily.
Stir the sample.
The moving average count is few.
Change dF (moving average count) to a larger
value.
A measured value
is high.
The sensor head is clogged with solids and
debris.
z
Remove solids.
z
If sludge flows in only one direction, orient the
tip of the detector toward the downstream side.
A measured value
is negative.
(at the time of zero
calibration)
The instrument is drifting.
z
There is no problem with some minuses.
Continue zero calibration as is.
There were causes that decreased
transmitted light during the previous zero
calibration.
z
The sensor head was dirty.
z
The zero water had turbidity.
z
The water temperature was different.
z
Perform zero calibration with clean water.
z
Remove any oil residue prior to zero
calibration.
z
Use zero water at a normal temperature (15
°
C
to 30
°
C) for calibration.
A measured value
does not vary.
Instructions are under Hold.
Release the HOLD mode and establish the Meas
Mode.
The sensor head is clogged with solids and
debris.
Remove foreign matter.
The value of zero
water is high at
calibration.
z
The sensor head is dirty.
z
An abnormality was found in the inside of
the sensor head.
z
Remove all dirt from the sensor head.
z
Contact us.
The instrument
does not operate
normally.
z
An abnormality was found in the motion of
a substrate.
z
The light source does not light up (actually
blink).
z
Check the connecting wires of the detector and
converter cables again.
z
The lighting (LED blinking) can be checked
with a digital camera image. If the LED is not
lighting up, contact us.
There is no power.
z
The power supply voltage falls outside the
rated voltage range.
z
There is a wiring problem.
z
The HU-200SS SS-90 has an internal
problem.
z
Check the power supply voltage.
z
Check the power wiring.
z
Contact us.
