Siemens SIMATIC S7-200 System Manual page 437

Definitions of the Analog Specifications
Accuracy: deviation from the expected value on a given point
-
Resolution: the effect of an LSB change reflected on the output.
-
Table A-23 EM 231 and EM 235 Specifications
Full Scale Input Full Scale Input
Range % of Full Scale
0 to 5 V
0 to 20 mA
0 to 10 V
± 2.5 V
± 5 V
0 to 50 mV
0 to 100 mV
0 to 500 mV
0 to 1 V
0 to 5 V
0 to 20 mA
0 to 10 V
± 25 mV
± 50 mV
± 100 mV
± 250 mV
± 500 mV
± 1 V
± 2.5 V
± 5 V
± 10 V
1
Measurements made after the selected input range has been calibrated.
2
The offset error in the signal near zero analog input is not corrected, and is not included in the accuracy specifications.
3
There is a channel-to-channel carryover conversion error, due to the finite settling time of the analog multiplexer. The maximum carryover
error is 0.1% of the difference between channels.
4
Mean accuracy includes effects of non-linearity and drift from 0 to 55 degrees C.
5
Analog input accuracy may deviate up to +/- -10% of full scale when subjected to severe RF interferences such as specified in the product
standard EN 61131- -2:2007. Following the recommended installation guidelines on the previous page can minimize unintended
disturbances on analog inputs. For high frequency immunity it is recommended that the cable shield be terminated at both ends.
1
Repeatability
Counts
EM 231 Specifications
± 0.075% 0.075%
EM 235 Specifications
± 0.075% 0 0 5%
± 0.075% ± 0.075%
Technical Specifications
Mean (average) Accuracy
% of Full Scale
± 24 24 ± 0.1% 0.1%
± 48 ± 48 ± 0.05% ± 0 05%
± 0.25%
± 0.2%
± 24
± 0.05% 0 05%
± 0.25%
± 0.2%
± 0.1%
± 48 ± 48
± 0.05% ± 0 05%
Appendix A
1,2,3,4,5
Counts
± 32 32
± 80
± 64
± 16 6
± 160
± 128
± 64
± 32 ± 32
423