MemoTrans
31
11.3.6 Delta Zero Point/Operating Point
pH, ISFET, Oxygen
Path:
Application
Sensor
Extended setup
Diagnostic settings
Function
Options
Info
pH, pH/ORP, ISFET
Delta zero point/
operating point (ISFET)
The device determines the difference between the last calibra-
tion and the penultimate calibration, and issues a warning or
an alarm depending on the setting configured. The difference
is an indicator for the condition of the sensor.
Function
Selection
• Off
• On
Factory setting
Off
Switches the function on or off
Warning limit
pH 0.00
…
2.00 (pH glass)
1
…
200 mV (ISFET)
Factory setting
pH 0.50 / 10 mV
Specify your limit values for monitoring the slope differential.
Diagnostics code and associated message text:
520
Sensor calibration
(pH glass)
522
Sensor calibration
(ISFET)
Oxygen
Function
Selection
• Off
• On
Factory setting
Off
Switches the function on or off
Warning limit
0.0
…
10.0 nA
Factory setting
1.0 nA
Specify the limit values for zero point monitoring in your
sensor. Diagnostics code and associated message text:
520
Sensor calibration
11.3.7 Operating Hours Limits
Path:
Application
Sensor
Extended setup
Diagnostic settings
Function
Options
Info
Limits operating hours
The total operating time of the sensor and its use under
extreme conditions is monitored. If the operating time exceeds
the defined threshold values, the device issues a
corresponding diagnostics message.
Function
Selection
• Off
• On
Factory setting
Off
On
: The operation of the sensor under extreme conditions is
monitored, recorded in the sensor, and diagnostics messages
are displayed on the controller.
Off:
No diagnostics messages. However, the time the sensor
operates under extreme conditions is recorded in the sensor
and can be read in the sensor information in the diagnostics
menu.
Operating time
Factory setting
Dependent on sensor
Operating time > 80 °C
Factory setting
Dependent on sensor
Diagnostics code and associated message text:
193
Operating time
Operating time > 80 °C
< 100 nS/cm
Factory setting
Dependent on sensor
Conductivity sensors only