Linear Temperature Compensation "T.lin; Saving A Measured Value With The Hold Function (Hld) - JUMO 202710/30 Operating Manual

5 Measuring

5.7.2 Linear temperature compensation "t.Lin"

Conductivity calculation within the device
Calculating the temperature coefficient
5.8

Saving a measured value with the hold function (HLD)

18
If the temperature compensation type is not precisely known, the "linear tem-
perature compensation" is used in practice (see "Parameter "t.Lin": compen-
sation coefficient", page 25). This involves making the simplified assumption
that the ratio of the temperature to the concentration will take a linear trajec-
tory across the measuring range being considered.
The conductivity is hereby calculated using the following equation. In this
regard, the parameter "t.Lin" corresponds to the formula value "TK
A temperature coefficient can be calculated, for example, by determining the
conductivity of a solution at 2 temperatures (T1 and T2) with the temperature
compensation switched off (t.Cor = oFF).
NOTE!
Temperature coefficients of around 2.0 %/K are most common.
The device features a "HOLD" function for saving a measured value.
Depending on the device configuration (see "Parameter "Auto HLD": auto-
matic saving of a measured value", page 27), the measured value can be
saved either by pressing the
value is reached.
When the measured value has been saved successfully, the message "HLD"
appears on the device display.
Press the key again to delete the saved value.
When automatic saving is activated, the next stable measured value will sub-
sequently be saved.
LF = Conductivity at reference temperature
Tref
TK = Linear temperature coefficient
lin
LF = Uncompensated conductivity at
Tx
current temperature
Tx = Current temperature
Tref = Reference temperature
TK = Linear temperature coefficient
lin
LF = Conductivity at temperature T1
T1
LF = Conductivity at temperature T2
T2
key or automatically when a stable measured
".
lin