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Siemens Desigo Desigo Room automation - Engineering, mounting and installation CM111043en_14
Smart Infrastructure Wiring of field devices (without bus) 2020-10-30
T1 sensors: Measured value error due to line resistance:
0.2
0
-0.1 100 200 300
1 mm²
L [m]
0.4
0.6
0.8
F [K]
10762d055
1,5 mm
²
2,5 mm
²
0,6 mm Ø
1.0
Formula: F =
10
1
A57
L2
-
·
·
A Cable cross-section in mm
2
F Measured temperature error in K
L Cable length in m
Measured value error of NTC sensors due to line resistance:
The sensors are highly non-linear. But thanks to the high sensor resistance the
errors are very small.
Error compared to T1:
NTC 100K
NTC10K
NTC3K
20°C x 0.01 x 0.1 x 0.3
100°C x 0.1 x 1 (~ equal) - -
Resistance transmitters (potentiometers):
Measured value error due to line resistance
2
0
-1 100 200 300
1 mm
²
L [m]
4
6
8
F [Ohm]
10762d036
1,5 mm
²
2,5 mm
²
0,6 mm Ø
Formula: F =
1
57
2
-
·
·
A
L
A Cable cross-section in mm
2
F Measurement error in ohms, due to line resistance (2RL for supply and return
conductor)
L Cable length in m
Measured value error
T1 sensors
Key
Measured value error
NTC sensor
Measured value error
Resistance transmitters
Key