Technical specifications
A.5 Analog signal modules
Easy Book
Manual, 05/2009, A5E02486774-01
113
A.5
Analog signal modules
The following specifications provide a sample of the analog SM modules available for S7-
1200. Refer to the S7-1200 system manual for more information.
Sample analog signal modules
General
SM 1231
AI 4x13bit
SM 1234
AI 4x13bit AQ 2x14bit
SM 1232
AQ 2x14bit
Number and type of inputs
(Selectable in groups of 2)
4 Voltage or Current
(differential)
4 Voltage or Current
(differential)
0
Number and type of outputs
0
2 voltage or current
2 voltage or current
Dimensions W x H x D
45 x 100 x 75 (mm)
45 x 100 x 75 (mm)
45 x 100 x 75 (mm)
Weight
180 grams
220 grams
180 grams
Power dissipation
1.5 W
2.0 W
1.5 W
Current consumption (SM Bus)
80 mA
80 mA
80 mA
Current consumption (24 VDC)
45 mA
60 mA (no load)
45 mA (no load)
Analog inputs
Description
Type of inputs
Voltage or Current (differential), selectable in groups of 2
Range
±10 V, ±5 V, ±2.5 V, or 0 to 20 mA
Full scale range (data word)
-27,648 to 27,648
Overshoot/undershoot range
(data word)
1
Voltage: 32,511 to 27,649 / -27,649 to -32,512
Current: 32,511 to 27,649 / 0 to -4864
Overflow/underflow (data word)
1
Voltage: 32,767 to 32,512 / -32,513 to -32,768
Current: 32,767 to 32,512 / -4865 to -32,768
Resolution
12 bits + sign bit
Maximum withstand voltage/current
±35 V / ±40 mA
Smoothing
2
None, weak, medium, or strong
Noise rejection
3
400, 60, 50, or 10 Hz
Impedance
≥ 9 MΩ (voltage) / 250 Ω (current)
Isolation (field side to logic)
None
Accuracy (25°C / 0 to 55°C)
±0.1% / ±0.2% of full scale
Analog to digital conversion time
625 μs (400 Hz rejection)
Common mode rejection
40 dB, DC to 60 Hz
Operational signal range
Signal plus common mode voltage must be less than +12 V and greater
than -12 V
Cable length (meters)
10 meters, twisted and shielded
1
Refer to the S7-1200 system manual for voltage and current representations of the analog inputs.
2
Refer to the S7-1200 system manual for step response times of the analog inputs.
3
Refer to the S7-1200 system manual for sample rates of the analog inputs.