Advertisement
Section 4
DNP3 parameters
4.1.3
20
App layer fragment is the application layer fragment size in bytes.
CROB select timeout is the DNP3 selecting before operating timer.
Unsolicited mode parameters
UR mode Unsolicited responses mode may be set to enable or disable. If enabled,
the initial unsolicited message is sent when the master opens a connection to the
IED, the first time after a IED reboot. All other unsolicited response parameters are
irrelevant if UR mode is disabled.
Enabling UR mode on a serial multidrop line is not recommended.
Collisions will result from multiple IEDs reporting concurrent
events. Although the DNP3 application layer will recover, collision
recovery can create significant traffic.
UR retries is the number of times the slave will resend the unsolicited response if it
is not confirmed by the master station.
UR TO is the unsolicited response timeout period in milliseconds. This timeout
period starts after App confirm TO expires. A new unsolicited response is
transmitted when UR TO expires. Application layer confirmations received from
the master during the UR TO period are not acknowledged by the IED.
UR offline interval is the unsolicited message offline interval in minutes. Offline
interval starts after the last UR retry. Offline interval never starts when UR retries
= 65535 (0xFFFF).
UR Class 1,2,3 Min events are the class 1, 2 or 3 number of events that must
accumulate before they are sent as unsolicited messages, unless the UR Class 1,2,3
TO expires causing the transmission of the events.
UR Class 1,2,3 TO is the time in ms, that class 1, 2 or 3 events are delayed before
being sent out, unless a count of UR Class 1,2,3 Min events have accumulated
causing the transmission of the events.
Legacy master UR provides compatibility to some older DNP3 masters. When set
to disabled, the slave follows the DNP3 standard, sending its first unsolicited
message after a connection has been established following IED reboot. The master
is expected to send the Enable/Disable Unsolicited messages command to the IED.
When Legacy master UR is enabled, the IED does not send the initial unsolicited
message. Unsolicited responses are sent without the need of the Enable Unsolicited
command. The master still needs to open a connection for the slave to start sending
unsolicited messages. Unsolicited mode needs to be enabled for this parameter to
be operational.
Legacy master UR allows non-standards compliant behavior.
1MRS757820 B
Recloser Protection and Control RER615
Communication Protocol Manual
Advertisement
