Siemens SIMATIC ET 200S, Руководство пользователя

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Response Times
D-6
ET 200S Distributed I/O System
EWA-4NEB 780602402-12
D.5 Response times for analog input modules
Conversion time
The conversion time comprises the basic conversion time and the processing time
for the wire break monitoring diagnosis (see the technical specifications for the
2AI TC STANDARD in Section 12.16 and 2AI TC HIGH FEATURE, Section 12.17).
In integrative conversion processes, the integration time is included directly in the
conversion time.
Cycle time
The analog/digital conversion and the transfer of the digitized measured values to
memory or to the backplane bus take place sequentially. In other words, the analog
input channels are converted one after the other. The cycle time, that is, the time
until an analog output value is converted again, is the sum of the conversion times
of all the activated analog output channels of the analog input modules. You should
deactivate unused analog input channels during parameter assignment in order to
reduce the cycle time. The conversion and integration time for a deactivated
channel is 0.
Fig. D-5 provides an overview of how the cycle time for an n-channel analog input
module is made up.
Channel 0 conversion time
Channel 1 conversion time
Cycle time
Figure D-5 Cycle time of the analog input module