Siemens SIMATIC ET 200eco PN, Руководство по эксплуатации

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F.2 Response times for analog output device
Conversion time
The conversion time of the analog output channels includes the transfer of digitized output
values from internal memory, and their digital-to-analog conversion.
Cycle time
The analog output channels are converted for the device with an execution time plus the
sequential conversion time for channels 0, 1, 2, and 3.
The cycle time, i.e., the time until an analog output value is converted again, is the sum of
the conversion times of all the activated analog output channels and of the processing time
of the analog output device. You should deactivate unused analog output channels during
parameter assignment in order to reduce the cycle time. The conversion time for a
deactivated channel is 0 ms.
The following figure provides you with an overview of the cycle time elements for an analog
output device.
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Figure F-2 Cycle time of analog output modules
Settling time
The settling time (t
2
to t
3
)—that is, the time from the application of the converted value until
the specified value is reached at the analog output—depends on the load. We therefore
distinguish between resistive, capacitive, and inductive loads.
Response time
The response time (t
1
to t
3
)—that is, the time from the application of the digital output values
in internal memory until the specified value is reached at the analog output—is, in the most
unfavorable case, the sum of the cycle time and the settling time. The worst case scenario is
when the analog channel has been converted immediately before a new output value is
transferred and is not converted again until all other channels have been converted (cycle
time).
260
ET 200eco PN
Operating Instructions, 06/2022, A5E01250250-AN
Response times for analog input device and output device
F.2 Response times for analog output device