Measured-Value Representation - Siemens S5-135U/155U System Manual

Analog Input/Output Modules
9.4.8

Measured-Value Representation

Measured-Value
(rated input ranges 0 to 1 V, 0 to 10 V, 0 to 20 mA, 4 to 20 mA)
Representation as
Value and Sign
Units Rated Range
0...10 0...1 V 0... 20
V mV mA
2047 19.99 1999 39.98
1536 15.00 1500 30.00
1535 14.99 1499 29.98
1280
1025 10.01 1001 20.02
1024 10.00 1000 20.00
1023 9.99 999.02 19.98
512 5.00 500.00 10.00
511 4.99 499.00 9.98
256 0.976
1 0.098 0 0.02
0 0 – 0
– 1 – 0.976 –0.02
– 51 0.098 –50 –1
– 0.5
1)
2)
3)
4)
5)
OV = Overflow bit
Shunt Resistor A 50 ohm shunt resistor is used for the 0 to 20 mA range; for 4 to 20 mA,
the resistor value is 62.5 ohms.
The shunt resistors are permanently fitted to the 463 analog input module.
Broken wire detection is not possible.
For the 4 to 20 mA current measuring range, a broken wire can be detected
with currents > 3 mA.
Current Limiting
If the positive and negative terminals of the transducer are short-circuited
when two-wire transducers are used (4 to 20 mA), the current is limited to
approximately 28 mA. Until the thermal current limiting circuit responds
(about 3 s) a short-circuit current of about 250 mA flows; this sets the
overflow bit for the short-circuited channel for this duration.
Load Voltage The failure of the load voltage can be detected from the result of encoding
(values < -51 units).
9-46
4...20 4...20 7 6
1) 2) 11 10
mA mA 2 2
35.98 31.98 0 1
28.00 24.00 0 1
27.98 23.98 0 1
20.00 0 1
20.02 16.02 0 1
20.00 16.00 0 1
19.98 15.98 0 0
12.00 8.00 0 0
11.98 7.98 0 0
4.00 0 0
4.0156 0.0156 0 0
4 0 0 0
3.9844 –0.015 1 1
3.184 6 1 1
–0.816
With data format setting 0 to 1023 (switch on module)
With data format setting 256 to 1279 (switch on module)
Overflow
Overrange
Rated range
Byte 0 Byte 1
5 4 3 2 1 0 7 6 5 4
9 8 7 6 5 4 3 2 1 0
2 2 2 2 2 2 2 2 2 2
1 1 1 1 1 1 1 1 1 1
1 0 0 0 0 0 0 0 0 0
0 1 1 1 1 1 1 1 1 1
0 1 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 1
0 0 0 0 0 0 0 0 0 0
1 1 1 1 1 1 1 1 1 1
1 0 0 0 0 0 0 0 0 0
0 1 1 1 1 1 1 1 1 1
0 1 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 1
0 0 0 0 0 0 0 0 0 0
1 1 1 1 1 1 1 1 1 1
1 1 1 1 0 0 1 1 0 1
C79000-G8576-C199-06
3 2 1 0
0 0 0 OV
3)
0 0 0 1
0 0 0 1
4)
0 0 0 0
0 0 0 0
0 0 0 0
5)
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
System Manual