GE 869 Communications Manual page 28

DNP COMMUNICATION
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DNP UNSOL RESPONSE FUNCTION
Range: Enabled, Disabled
Default: Disabled
Should be "Disabled" for RS485 applications since there is no collision avoidance
mechanism. Unsolicited response settings is hidden if the communication card is not
present, as DNP runs only on RS485 in this case.
DNP UNSOL RESPONSE TIMEOUT
Range: 0 to 60 s in steps of 1 s
Default: 5 s
Sets the time the 869 waits for a DNP master to confirm an unsolicited response.
DNP UNSOL RESPONSE MAX RETRIES
Range: 1 to 255 in steps of 1
Default: 10
Sets the number of times the 869 retransmits an unsolicited response without receiving
confirmation from the master; a value of "255" allows infinite re-tries.
DNP UNSOL RESPONSE DEST ADDRESS
Range: 0 to 65519 in steps of 1
Default: 1
Sets the DNP address to which all unsolicited responses are sent. The IP address to
which unsolicited responses are sent is determined by the 869 from the current TCP
connection or the most recent UDP message.
DNP TIME SYNC IIN PERIOD
Range: 1 to 10080 min in steps of 1 min
Default: 1440 min
This setting determines how often the Need Time Internal Indication (IIN) bit is set by the
869 . Changing this time requires the DNP master to send time synchronization
commands more or less often, as this setting time period.
If the requirement for time synchronization is more than a couple of seconds the user is
advised to consider time-sync via other means such as IRIG-B or 1588, given network
asymmetry, the consistency of the network latency, clock drift and additional delays due to
routers located between the client and the 869 , all of which contribute errors.
DNP MESSAGE FRAGMENT SIZE
Range: 30 to 2048 in steps of 1
Default: 240
This setting determines the size (maximum length of frame), in bytes, at which message
fragmentation occurs. Large fragment sizes allow for more efficient throughput; smaller
fragment sizes cause more application layer confirmations to be necessary which can
provide for more robust data transfer over noisy communication channels.
DNP OBJECT 1(2) DEFAULT VARIATION
Range: 1, 2
Default: 2
These settings allow the user to select the DNP default variation number for object types
1, 2, 20, 21, 22, 23, 30, and 32. The default variation refers to the variation response when
variation 0 is requested and/or in class 0, 1, 2, or 3 scans. The DNP binary outputs
typically map one-to-one to IED data points. That is, each DNP binary output controls a
single physical or virtual control point in an IED. In the 869 relay, DNP binary outputs are
mapped to virtual inputs.
869 MOTOR PROTECTION SYSTEM – COMMUNICATIONS GUIDE
CHAPTER 4: DNP 3