Page 1 of 5 Home Full Navigation Path Siemens Industry Catalogue Automation technology Automation Systems SIMATIC Industrial Automation Systems Controllers SIMATIC S7 modular controllers S7-1200 Signal modules Analog modules SM 1231 thermocouple module URL: https://eb.automation.siemens.com/goos/catalog/pages/print PreviewProductData.aspx Current View: Product Information e.g. Dear Customer Overview For the convenient recording of temperatures with great accuracy 7 common thermocouple types can be used Also for the measurement of analog signals with a low level (±80 mv) Can easily be retrofitted to existing plant Application The SM 1231 thermocouple modules enable temperatures to be measured with high precision using established thermocouples. In addition, low level analog signals in the ±80 mv range can be recorded. The SM 1231 thermocouple modules can be used with the CPUs of the S7-1200 series. Function Different measurement ranges: Thermocouples of types J, K, T, E, R, S and N; analog signal recording ±80 mv. Check for open lines. Compensation of the cold connecting point: Faults caused by contact voltages at the connection between thermocouple and module are prevented; when recording analog signals (±80 mv), the compensation is automatically deactivated. Temperature scaling: The measured temperature can be shown in C or F. Design The SM 1231 thermocouple modules exhibit the same structural features as the other modules of the S7-1200 series: Mounting on a DIN rail: The modules are snapped onto the rail just to the right of the CPU and connected to one another and with the CPU
Page 2 of 5 12xx by means of the integral backplane bus. Direct mounting: Drilled holes permit the module to be bolted directly to walls. This type of mounting is recommended for applications subject to strong vibrations. Thermocouples: Four thermocouples each of types J, K, T, E, R, S and N can be used. They are connected directly to the module without amplifiers. Mounting location: For maximum possible measurement and repeat accuracy, the thermocouple modules should be mounted in locations with low temperature variations. Technical specifications 6ES7 231-5QD30-0XB0 6ES7 231-5QF30-0XB0 Product type designation SM1231 TC 4x16 bit SM 1231 TC 8x16bit CiR - Configuration in RUN Reparameterization possible in RUN 24 V DC Yes Yes Current consumption, typ. 40 ma from backplane bus 5 V DC, typ. 80 ma 80 ma Power losses Power loss, typ. 1.5 W 1.5 W Analog inputs Number of analog inputs 4; Thermocouples 8; Thermocouples permissible input frequency for current input (destruction limit), max. ± 35 V ± 35 V Technical unit for temperature measurement adjustable Input ranges Degrees Celsius/degrees Fahrenheit Degrees Celsius/degrees Fahrenheit Thermocouple Yes; J, K, T, E, R, S, N, C, TXK/XK(L); voltage range: +/-80 mv Yes; J, K, T, E, R, S, N, C, TXK/XK(L); voltage range: +/-80 mv Input ranges (rated values), voltages -80 mv to +80 mv Yes Yes Input resistance (-80 mv to +80 mv) Input ranges (rated values), thermoelements >=1MOhm >=1MOhm Type C Yes Yes Type E Yes Yes Type J Yes Yes Type K Yes Yes Type N Yes Yes Type R Yes Yes
Page 3 of 5 Type S Yes Yes Type T Yes Yes Type TXK/TXK(L) to GOST Yes Yes Thermocouple (TC) permissible input voltage for voltage input (destruction limit), max. Temperature compensation Temperature compensation parameterizable Analog value creation +-35V +-35V Measurement principle Integrating Integrating Integrations and conversion time/ resolution per channel Resolution with overrange (bit including sign), max. 15 bit; + sign 15 bit; + sign Integration time, parameterizable Interference voltage suppression for interference frequency f1 in Hz 85 db at 50/60/400 Hz 85 db at 50/60/400 Hz Analog value generation (in isochronous mode) Smoothing of measured values parameterizable Yes Yes Errors/accuracies cold connection point +/-1.5 C Temperature error (relative to input area) Interference voltage suppression for f = n x (fl +/- 1%), fl = interference frequency 25 C ±0.1% to 55 C ±0.2% total measurement range 25 C ±0.1% to 55 C ±0.2% total measurement range Common mode interference, min. 120 db 120 db Interrupts/diagnostics/status information Alarms Alarms Yes Yes Diagnostic alarm Yes Yes Diagnoses Diagnostic functions Yes; can be read out Yes; can be read out Monitoring the supply voltage to the electronics Yes Yes Wire break Yes Yes Diagnostics indication LED
Page 4 of 5 for status of the inputs Yes Yes for maintenance Yes Yes Climatic and mechanical conditions for storage and transport Climatic conditions for storage and transport Free fall Drop height, max. (in packaging) Temperature 0.3 m; five times, in dispatch package 0.3 m; five times, in dispatch package Permissible temperature range -40 C to +70 C -40 C to +70 C Air pressure acc. to IEC 60068-2-13 Permissible air pressure 1080 to 660 hpa 1080 to 660 hpa Relative humidity Permissible range (without condensation) at 25 C 95% 95% Mechanical and climatic conditions during operation Climatic conditions in operation Temperature Permissible temperature range Air pressure acc. to IEC 60068-2-13 0 C to 55 C horizontal mounting 0 C to 45 C vertical mounting 0 C to 55 C horizontal mounting 0 C to 45 C vertical mounting Permissible air pressure 1080 to 795 hpa 1080 to 795 hpa Pollutant concentrations SO2 at RH < 60% without condensation S02: < 0.5 ppm; H2S: < 0.1 ppm; RH < 60% condensation-free S02: < 0.5 ppm; H2S: < 0.1 ppm; RH < 60% condensation-free IP20 Yes Yes Standards, approvals, certificates CE mark Yes Yes C-TICK Yes Yes FM approval Yes Yes Connection method required front connector Yes Yes Mechanics/material Type of housing (front) Plastic Yes Yes Dimensions and weight Dimensions Width 45 mm 45 mm
Page 5 of 5 Height 100 mm 100 mm Depth 75 mm 75 mm Weight Weight, approx. 180 g 220 g More information Brochures Information available for download on the Internet: http://www.siemens.com/simatic/printmaterial