Siemens Simatic S7-1500/ET 200MP System Manual page 67

System overview
3.6 Input and output modules
Scaling of the measured values of the analog input module AI 8xU/I HF
With measured value scaling, you display the user data of the module in REAL format (32-bit
floating point) instead of S7 format. You can thus directly assign a technological variable to
the analog value of the module. The conversion is made directly in the module, which saves
power and cycle time in the CPU.
You can combine the measured value scaling with the measuring range adjustment. In this
case, the measuring range is adjusted first and then the representation of the measured
value is scaled.
Calibration in runtime
The following analog modules offer you the calibration function at runtime:
● AI 8xU/I/RTD/TC ST
● AI 8xU/I HS
● AI 4xU/I/RTD/TC ST
● AI 4xU/I/RTD/TC / AQ 2xU/I ST
The calibration compensates for influences on the measuring result by cables and/or
temperature. A calibration checks the process values output by the analog input module,
determines the deviation from the actual values and compensates for measuring errors.
Typical use:
● for plants in which sensors detect relatively small voltages or currents
● for applications which require regular calibration for all components in a measuring circuit.
Oversampling of the AI 8xU/I HS analog input module
Oversampling divides a PROFINET bus cycle into equidistant bus sub-cycles. This requires
isochronous mode.
Oversampling acquires data with high time resolution but without using an extremely short
PROFINET bus cycle and thus fast CPU cycles. Use for quality-monitoring measurements,
for example when recording pressure trends during the blowing process of PET bottle
production.
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Automation system
System Manual, 12/2017, A5E03461182-AE