General information
Product type designationSM 1231, AI 8x 14 bit
based on6ES7231-4HF50-0XB0
Supply voltage
Rated value (DC)24 V
permissible range, lower limit (DC)20.4 V
permissible range, upper limit (DC)28.8 V
Input current
Current consumption, typ.45 mA
from backplane bus 5 V DC, typ.75 mA
Power loss
Power loss, typ.2.5 W
Analog inputs
Number of analog inputs8; Current or voltage differential inputs
permissible input voltage for voltage input (destruction limit), max.35 V
permissible input current for current input (destruction limit), max.40 mA
Cycle time (all channels) max.1.25 ms; at 400 Hz rejection
Input ranges
VoltageYes; ±10V, ±5V, ±2.5V
CurrentYes; 4 to 20 mA, 0 to 20 mA
ThermocoupleNo
Resistance thermometerNo
ResistanceNo
Input ranges (rated values), voltages
-10 V to +10 VYes
— Input resistance (-10 V to +10 V)≥1 MOhm
-2.5 V to +2.5 VYes
— Input resistance (-2.5 V to +2.5 V)≥1 MOhm
-5 V to +5 VYes
— Input resistance (-5 V to +5 V)≥1 MOhm
Input ranges (rated values), currents
0 to 20 mAYes
— Input resistance (0 to 20 mA)< 290 Ω, > 270 Ω
4 mA to 20 mAYes
— Input resistance (4 mA to 20 mA)< 290 Ω, > 270 Ω
Cable length
shielded, max.100 m; shielded, twisted pair
Analog value generation for the inputs
Measurement principlesuccessive approximation
Integration and conversion time/resolution per channel
Resolution with overrange (bit including sign), max.13 bit; + sign
Integration time, parameterizableYes
Interference voltage suppression for interference frequency f1 in Hz40 dB, DC to 60 Hz
Smoothing of measured values
parameterizableYes
Step: NoneYes
Step: lowYes
Step: MediumYes
Step: HighYes
Errors/accuracies
Temperature error (relative to input range), (+/-)25 °C ±0.1 % / -40 °C to 70 °C ±0.3 % of the full-scale deflection
Basic error limit (operational limit at 25 °C)
Voltage, relative to input range, (+/-)0.1 %
Current, relative to input range, (+/-)0.1 %
Interference voltage suppression for f = n x (f1 +/- 1 %), f1 = interference frequency
Common mode voltage, max.12 V
Interrupts/diagnostics/status information
Diagnostics functionYes
Alarms
Diagnostic alarmYes
Diagnoses
Monitoring the supply voltageYes
Wire breakYes
Diagnostics indication LED
DIAG LEDYes
for status of the inputsYes
Degree and class of protection
IP degree of protectionIP20
Standards, approvals, certificates
Siemens Eco Profile (SEP)Siemens EcoTech
Ecological footprint
environmental product declarationYes; type 2 acc. to ISO 14021
Global warming potential
— global warming potential, (total) [CO2 eq]32.2 kg
— global warming potential, (during production) [CO2 eq]7.96 kg
— global warming potential, (during operation) [CO2 eq]24.5 kg
— global warming potential, (after end of life cycle) [CO2 eq]-0.358 kg
Free fall
Fall height, max.0.3 m; five times, in product package
Ambient temperature during operation
min.-40 °C
max.60 °C; at max. voltages and max. specifications
horizontal installation, min.-40 °C; incl. condensation/frost
horizontal installation, max.70 °C; at rated voltages, 50 % of max. specification and alternate IO active
vertical installation, min.-40 °C
vertical installation, max.50 °C; at rated voltages, 50 % of max. specification and alternate IO active
Ambient temperature during storage/transportation
min.-40 °C
max.70 °C
Air pressure acc. to IEC 60068-2-13
Operation, min.540 hPa
Operation, max.1 140 hPa
Storage/transport, min.540 hPa
Storage/transport, max.1 140 hPa
Altitude during operation relating to sea level
Installation altitude, min.-1 000 m
Installation altitude, max.5 000 m; Restrictions for installation altitudes > 2 000 m, see manual
Relative humidity
With condensation, tested in accordance with IEC 60068-2-38, max.100 %; RH incl. condensation / frost (no commissioning in bedewed state), horizontal installation
Vibrations
Vibration resistance during operation acc. to IEC 60068-2-63.5 mm from 5 - 8.4 Hz, 1g from 8.4 - 150 Hz
Operation, tested according to IEC 60068-2-6Yes
Shock testing
tested according to IEC 60068-2-27Yes; IEC 68, Part 2-27 half-sine: strength of the shock 15 g (peak value), duration 11 ms
Coolants and lubricants
— Resistant to commercially available coolants and lubricantsYes; Incl. diesel and oil droplets in the air
Use in stationary industrial systems
— to biologically active substances according to EN 60721-3-3Yes; Class 3B2 mold, fungus and dry rot spores (with the exception of fauna); Class 3B3 on request
— to chemically active substances according to EN 60721-3-3Yes; Class 3C4 (RH < 75%) incl. salt spray acc. to EN 60068-2-52 (severity degree 3)
— to mechanically active substances according to EN 60721-3-3Yes; Class 3S4 incl. sand, dust
Use on ships/at sea
— to biologically active substances according to EN 60721-3-6Yes; Class 6B2 mold, fungal and dry rot spores (excluding fauna)
— to chemically active substances according to EN 60721-3-6Yes; Class 6C3 (RH < 75%) incl. salt spray acc. to EN 60068-2-52 (severity degree 3).
— to mechanically active substances according to EN 60721-3-6Yes; Class 6S3 incl. sand, dust
Usage in industrial process technology
— Against chemically active substances acc. to EN 60654-4Yes; Class 3 (excluding trichlorethylene)
— Environmental conditions for process, measuring and control systems acc. to ANSI/ISA-71.04Yes; Level GX group A/B (excluding trichlorethylene; harmful gas concentrations up to the limits of EN 60721-3-3 class 3C4 permissible); level LC3 (salt spray) and level LB3 (oil)
Conformal coating
Coatings for printed circuit board assemblies acc. to EN 61086Yes; Class 2 for high reliability
Protection against fouling acc. to EN 60664-3Yes; Type 1 protection
Military testing according to MIL-I-46058C, Amendment 7Yes; Discoloration of coating possible during service life
Qualification and Performance of Electrical Insulating Compound for Printed Board Assemblies according to IPC-CC-830AYes; Conformal coating, Class A
Connection method
required front connectorNo
Mechanics/material
PlasticYes
Dimensions
Width30 mm
Height125 mm
Depth100 mm
Weights
Weight, approx.175 g