User Manual

<16. COMMISSIONING OF SENCOM pH/ORP>
16-5
IM 12A01A02-01E 5th Edition : Oct. 31, 2013-00
n Temperature compensation
ThiscompensationofpHvalueisperformedontheNernstequation.
Two methods can be used: Automatic and Manual. Select Automatic when a temperature
element is used, or select Manual when a manually set temperature is used.
NOTE
When Manual is selected on the Temperature compensation, a process temperature should
be set in the “Manual temp.” A temperature shown on the Main display is this manually set
temperature.
n Reference temperature
SetareferencetemperaturetowhichthemeasuredpHvaluemustbecompensated.Normally
25°C is used, so this temperature is chosen as the default value.
n Process temperature compensation
Selectatemperaturecompensationmethod.“None”doesnotperformthetemperature
compensation.
If “pH” is selected in “Sensor type,” choose process temperature compensation from among
None,TC,Matrix,andNEN6411.If“ORP”isselectedin“Sensortype,”chooseitfromamong
NoneandTC.
l TC
This method uses the linear compensation function.
Itispossibletoadjustthetemperaturecoefcient(TC)factordirectly.Ifthetemperature
coefcientfactorofthesampleliquidisknownfromlaboratoryexperimentsorhasbeen
previously determined, it can be entered here.
ThisTCisapHvariationto1°C(∆pH/∆T).Adjustthevaluebetween-0.1to0.1pH/ºC.
In combination with the reference temperature setting, a linear compensation function is
obtained, which is suitable for all kinds of chemical solutions.
l Matrix
Matrixmeansatemperaturecompensationwhichusesthetemperaturecompensation
matrix.ThetemperaturecompensationmatrixisatableofpHvaluesatvarioustemperatures
correspondingtothepHvaluesatthestandardtemperature.Fordetails,seeAppendix1.
When the temperature or the precompensated pH value is out of the range of the temperature
compensationmatrix,thetemperaturecompensationerror(warning)willbeissued.Thisisnota
device error.
Inthiscase,however,thetemperaturecompensationisperformedbyextrapolation.
NOTE
TodisplaytheprecompensatedpHvalue,settheProcessTemp.Compensationto“None”.
SelectMeasurementsetup→Temp.compensation→ProcessTemp.Compensation.
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SENCOM