Siemens SIMATIC NET CP 1243-1 DNP3, Руководство по настройке

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Configuration
3.8 DNP3 parameters of the interfaces
Configuration - DNP3
54
Configuration Manual, 11/2018, C79000-G8976-C508-01
– Station:
In the station, the parameter is used to calculate the waiting times during connection
establishment.
With redundant paths, the following applies: If the acknowledgment is not received, the
transmission path is classified as disrupted.
Range of values: 0 ... 65535 s
Default: 5
With the setting 0 (zero), the function is disabled.
Data link layer
● Frame repetition
Maximum number of retries to send a frame if no acknowledgment is received from the
partner on the data link layer.
–
With serial connections, repetitions can be useful if the connection quality is not good.
– With Ethernet connections, it is recommended that you configure the value 0, since
required repetitions are carried out by the protocol implementation.
Range of values: 0 ... 255
Default setting: 0
With the setting 0 (zero), the function is disabled.
● Acknowledgment
Condition under which the module requests an acknowledgment of receipt from the
partner (sending of the "CONFIRMED_USER_DATA" function code):
–
Never
No acknowledgments are requested.
– Always
Acknowledgments are always requested.
– For segmentation
Acknowledgments are only requested for data frames which are divided into several
segments due to their length.
With Ethernet connections, the DNP3 specification recommends that acknowledgment
requests are not used on the data link layer.
On connections that are liable to disturbances, for example wireless links, the
configuration of acknowledgment requests can be useful on the data link layer.