Message
Please calibrate electrode
Active sensor cannot be deleted
Wrong buffer
Slope out of range
Offset out of range
Buffer temp. out of range
Standard temp. out of range
Temperature differs from setting
®
ISM
sensor communication error
Self-test failure
Wrong settings
Out of range
Wrong password
28
Maintenance
Description and Resolution
Calibration reminder has been switched on in the menu settings
and last calibration has expired.
Calibrate the electrode.
Deleting the calibration data of the selected sensor ID is not
possible, because it is currently the active sensor ID in the meter
shown on the display.
Enter new sensor ID in the menu settings.
Select another sensor ID from the list in the menu settings.
Meter cannot recognize the buffer or standard/buffer has been
used twice for calibration/two buffers differ less than 60 mV.
Make sure that you have the correct buffer and that it is fresh.
Make sure that the buffer has not been used more than once
during the calibration.
The calibration result is outside the following limits: Slope < 85%
or > 105%, Offset < -35 mV or > + 35 mV.
Make sure that you have the correct buffer and that it is fresh.
Check mV signal of electrode, clean or replace the electrode.
The ATC measured temperature is out of pH calibration buffer
range: 5 ... 50 °C or out of conductivity calibration range: 0...
35°C.
Keep the buffer/standard temperature within the range.
Change the temperature setting.
ATC measured temperature differs by more than 0.5°C from the
user-defined value/temperature range.
Keep the buffer/standard temperature within the range.
Change the temperature setting.
Data has not been transferred correctly between ISM
®
meter. Reconnect the ISM
Self-test has not been completed within 2 minutes or meter is
defective.
Restart self-test and finish within 2 minutes.
Contact METTLER TOLEDO service if problem persists.
Entered value differs by less than 1 pH unit/5°C from other preset
values.
Enter a higher/lower value in order to get a bigger difference.
Either entered value is out of range.
Enter a value which is within the range shown on display.
or
Measured value out of range.
Make sure the electrode wetting cap has been removed and
that the electrode is properly connected and placed in the
sample solution.
If no electrode is connected, put the shorting clip in the
socket.
The entered PIN is not correct.
Re-enter the PIN.
Reset to factory settings, all data and settings will be lost.
®
sensor and
sensor and try again.
SevenGo Duo pro™