wtw Multi 350i, Operating Manual

Page: 87 / 108

Multi 350i What to do if...
85
6.2 ISE measurement
Error message OFL
Obviously incorrect
measured values
Error message, Error
(invalid
calibration)
Warning [TempErr]
Warning [ISEErr]
Cause Remedy
– Measuring range exceeded – Dilute test sample
Cause Remedy
– Electrode not connected – Connect electrode
– Cable broken – Replace electrode
Cause Remedy
Ion-sensitive electrode:
– Moisture in the plug – Dry plug
– Electrode obsolete – Replace electrode
– Electrode unsuitable for the
range to be measured
– Use a suitable electrode
– Socket damp – Dry socket
Calibration procedure:
– Wrong sequence of standards
for three point calibration
– Select correct sequence
– Calibration standards do not
have the correct temperature
(max.
±
2 °C temperature
difference)
– Adjust the temperature of
the calibration standards
Cause Remedy
– Temperature difference
between measurement and
calibration greater than 2 K.
– Adjust the temperature of
the test sample
Cause Remedy
– Electrode voltage outside
calibrated range
– Recalibrate