Technical specifications
A.11 Thermocouple and RTD signal modules (SMs)
S7-1200 Programmable controller
System Manual, V4.2, 09/2016, A5E02486680-AK
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Selection tables for the SM 1231 thermocouple
The ranges and accuracy for the different thermocouple types supported by the SM 1231
Thermocouple signal module are shown in the table below.
Table A- 169 SM 1231 Thermocouple selection table
Normal range
3, 4
accuracy @ 25 °C
Normal range
1, 2
accuracy -20 °C
to 60 °C
E -270.0 °C -200.0 °C 1000.0 °C 1200.0 °C ±0.3 °C ±0.6 °C
B
Voltage -32512 -27648
27648
32511 ±0.05% ±0.1%
Thermocouple values below the under-range minimum value are reported as -32768.
Thermocouple values above the over-range minimum value are reported as 32767.
Internal cold junction error is ±1.5 °C for all ranges. This adds to the error in this table. The module requires at least 30
minutes of warm-up time to meet this specification.
In the presence of radiated radio frequency of 970 MHz to 990 MHz, the accuracy of the SM 1231 AI 4 x 16 bit TC may
Note
Thermocouple channel
Each channel on the Thermocouple signal module can be configured with a different
t
hermocouple type (selectable in the software during configuration of the module).