© 2016 Thorlabs
6 Operating Instruction
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In the channel menu the approximation method can be selected and the corresponding parameters
can be entered. Select the line
Steinh.-Hart or Exponential
The right soft key toggles between the two methods. Select the desired type and press
to
apply the setting.
Exponential method
The dependency between resistance and temperature of an NTC (thermistor) can be described by
the formulas:
with: R(T) Thermistor resistance at a given temperature T
R
0
Thermistor nominal resistance at temperature T
0
T
0
Nominal temperature (typ. 298.15 K = 25° C)
B
val
Energy constant
(Temperature always given in Kelvin)
For R
0
, T
0
and B
val
, please refer to the data sheet of the thermistor. To change the three
parameters select them one by one and change them to the desired value. Press
to apply
the setting. See also Changing Parameters .
Steinhart-Hart method
A further way of representing the relation between temperature and thermistor resistance is the
method according to Steinhart-Hart
with the three parameters C1, C2 and C3.
To change the three parameters in accordance with the actual thermistor, select them one by one
and set them to the desired value.
Pressing terminates the input and applies value.
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