IM 12B6C2-E-H
1. What is compensated for?
Temperature influences the sensitivity of the
glass electrode.
To nullify this effect the EXA PH200 has to
compensate the pH value with the formula
derived by Nernst.
To be able to do this the temperature has to
be measured as well. Either by a seperate
sensor or a temperature setting.
Temperature compensation can be set to
manual if the process is near pH 7 or at
fixed temperature.
2. How is it compensated?
The process temperature is measured with a
separate circuit connected to the temperatu-
re sensor (e.g. Pt1000 resis tor).
The resistance value of the temperature sen-
sor is calculated into the temperature value.
This value is used to calculate the compen-
sated value for the pH on the display.
3. Example
Setting the manual temperature compen
sation to a fixed setting of 30°C.
Press NO to change from default automatic
compensation to manual compensation.
The display will show TEMP °C and the
value can be adjusted to 30°C. Press ENT
to confirm the setting.
The display will show TEMP.MAN at the top
to indicate your choice.
4. Further Options
- Process temperature compensation (see
Service settings §7-3).
- Calibrating the temperature circuit (see
Service settings § 7-11).
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5-4. Temperature compensation
