ProSoft Technology MVI56-101S - Manual (Page 124)

Reference MVI56-101S ♦ ControlLogix Platform
User Manual IEC 60870-5-101 Slave Communication Module
Page 124 of 193 ProSoft Technology, Inc.
August 2, 2011
Monitor Data Transfer
In unbalanced mode, the polling procedure is initiated from the Master unit
through Class 1 and Class 2 requests. In general, ASDUs containing
periodic(cyclic) causes of transmission are typically assigned to be transmitted in
response to Class 2 requests from the Master. All ASDUs containing time-tagged
or spontaneous causes of transmission are typically assigned to be transmitted in
response to Class 1 requests. Other ASDUs with other causes of transmission of
low priority, such as background scans, may also be assigned to be transmitted
in response to Class 2 requests.
Typically, you should properly configure the group code for each monitor point to
define how the Master will poll for the point.
The module will periodically send all points configured for periodic/cyclic poll
(0x80000000) at every x milliseconds, where x is configured with the Cyclic Data
Transmission parameter: