Data Sheet

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Page 2
SHEATH RESISTANCE THERMOMETER
WITH FOUR WIRE CONNECTION M12 CON-MANTE
Evaluation
The evaluation of the sensor resistance usually
takes place through the voltage drop measured at
the sensor because of a constant measuring
current flowing through it. Hence, the change in
voltage ΔU is approximately proportional to the
change in resistance ΔR. For selection of the
measuring current, there must be a trade-off
between the achievable useful signal, which rises
with the measuring current which in turn also
increases the measuring error because of self
heating of the sensor.
Resistance characteristics
The hot resistance R of a platinum temperature
sensor at a given temperature T with the nominal
resistance R0 can be calculated as per the
following equations:
For temperature range between 0 and 100 °C, the
linear function (1st order polynomial) is
approximately valid where temperature is T (in °C):
R = R0 · (1 + a · T)
a = 3.85 · 10
-3
/ K
In the range up to 850°C, or with higher accuracy
requirements, also in the range between 0 and
100 °C, one uses a quadratic function for
linearisation (2nd order polynomial):
R = R0 · (1 + a · T + b · T2)
a = 3.9083 · 10
-3
/ K
b = -5.775 · 10
-7
/ K2
In the range below 0°C, one has to use a
polynomial of 4. level:
R = R0 (1 + a T + b T2 + c (T − 100 °C)·T3)
a = 3.9083 · 10
-3
/ K
b = -5.775 · 10
-7
/ K2
c = -4.183 · 10
-12
/ K4
Dimensional Drawing
Accuracy class
Due to the manufacturing tolerances, platinum
temperature sensors are divided into A and B
classes. These specify the dependence of
allowable temperature error ΔT of the real
temperature T. Error limits of class in °C:
Class A: ΔT = ± (0.15 °C + 0.002 · T)
Class B: ΔT = ± (0.30 °C + 0.005 · T)
1/3 Class B: ΔT = ± (1/3 · (0.30 °C + 0.005 · T))
1/10 Class B: ΔT = ± (1/10 · (0.30 °C + 0.005 · T))
For the 1/3 DIN and 1/10 DIN Class B laboratory
grade resistance, the applicable temperature range
is defined for the higher specified accuracy This
differs from the normally possible application
temperature range.
Connection layout
Ordering number format
CON – MANTE – PT100
- PT100 with PT100 Sensor
- PT1000 with PT1000 Sensor
Jacket resistance thermometer with four wire connection
Accessories Ordering No.
Connection cable 2M KAB-M12-2M
Connection cable 5M KAB-M12-5M
M12-Connection socket STEK M12