User Manual

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Siemens TX-I/O Engineering and installation guide CM110562en_13
Building Technologies Principles of electrical design 2019-05-15
10.12.2 Correcting the line resistance with [Icpt]
For analog inputs (measuring of temperature or resistance), most signal types are
calibrated for a line resistance of 1 Ohm.
Desigo: If the line resistance differs significantly from 1 Ohm, [Icpt] can be changed in
the AI block.
PROFINET BIM: The line resistance can be configured in the S7 HW Config Tool using
parameter "Compensation".
Resistance measuring
Line resistance
[Slpe]
[Icpt]
Delta Slope
Delta Intercept
AI PT1K385 (Europe)
0 Ohm
0.0259740
-259.480519
0
0.259740
Default = 1 Ohm
0.0259740
-259.740260
0
0
2 Ohm
0.0259740
-260.000000
0
-0.259740
3 Ohm
0.0259740
-260.259740
0
-0.519481
AI PT1K375 (USA)
0 Ohm
0.0266667
-266.400000
0
0.2667
Default = 1 Ohm
0.0266667
-266.666667
0
0
2 Ohm
0.0266667
-266.933333
0
-0.2667
3 Ohm
0.0266667
-267.209900
0
-0.5333
AI 2500 Ohm, AI PT1000
(0 ... 2500 Ohm)
0 Ohm
0.1
1
0
1
Default = 1 Ohm
0.1
0
0
0
2 Ohm
0.1
-1
0
-1
3 Ohm
0.1
-2
0
-2
AI 250 Ohm *)
0 Ohm
0.01
1
0
1
Default = 1 Ohm
0.01
0
0
0
2 Ohm
0.01
-1
0
-1
3 Ohm
0.01
-2
0
-2
AI PT100 (0 ... 250 Ohm)
*)
Default = 0 Ohm
0.01
0
0
0
1 Ohm
0.01
-1
0
-1
2 Ohm
0.01
-2
0
-2
3 Ohm
0.01
-3
0
-3
*)
TX-I/O modules with
island bus integration:
AI Pt100 4 wire is a 4-wire type Default line resistance = 0 Ohm
Do not compensate the line resistance!
AI 250 Ohm is a 2-wire type
Default line resistance = 1 Ohm
TX-I/O modules with inte-
gration via P-Bus-BIM:
Pt100_4 is a 4-wire type Default line resistance = 0 Ohm
Do not compensate the line resistance!
R250 is a 2-wire type, but it must be connected to
4 terminals with jumpers
Default line resistance = 0 Ohm
PT-I/O modules: P100 is a 4-wire type Default line resistance = 0 Ohm
Do not compensate the line resistance!