Operational Guide
29
Contaminated Buffer
“CONTAMINATED BUFFER” appears in order to alert
that the buffer could be contaminated. Refresh your
buffer and continue the calibration procedure.
Broken Temperature Sensor
If the temperature sensor should malfunction or break at any time, a temperature
of “25.0 ºC” will blink on the second LCD line and the
message “BROKEN TEMPERATURE SENSOR” will
appear on the third LCD line after leaving calibration.
The calibration will have the compensation at 25 ºC.
Replace probe if this occurs.
Note
: If this occurs during logging “25 ºC !” will appear in the CSV file.
Good Laboratory Practice (GLP) refers to a quality control function used to
ensure uniformity of sensor calibrations and measurements. The dedicated
GLP
key opens a file of the latest calibration information. Use the
qp
keys to
scroll the stored information. This includes the buffers used, temperature of the
buffer, time and date of the last calibration, the sensor serial number and the
calculated offset and percent slope. This information is available in Basic and
Standard Modes. This information is also included with every data log. Newest
calibration points report as a solid number, older calibration data (that is still
used) will be displayed blinking.
If calibration has not been performed, the instrument
displays a blinking “NO CAL” message.
The pH calibration offset and slope (the GLP slope is
the average of the calibration slopes; the percentage
is referenced to the ideal slope value at 25 ºC). The
condition and response indicators displayed are from
the last calibration.
Pressing the
qp
keys, the last calibration date (yyyy.
mm.dd) together with the current reading is displayed.
Calibration
Messages
pH GLP
Information
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