ABB 620 Series Manual page 27

1MAC459571-IB C
620 series ANSI
Communication Protocol Manual
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.
Legacy master SBO provides compatibility to some older DNP3 masters for the Select
Before Operate command. When disabled, DNP3 expects the application layer sequence
of the operate command to be the select command sequence + 1 modulo 16. When enabled
the IED ignores sequence number of the operate command. This situation might occur
when the master sends additional requests between the select and operate commands.
Legacy master SBO allows non-standards compliant behavior.
Additional parameters
Need time interval is the interval in minutes for setting the need time bit in the IIN. The IIN
need time bit requests the DNP3 master to send a time synchronization to the IED. When
set to 0 the need time IIN bit is never set, and DNP3 time synchronization is never
requested. The time synchronization source needs to be set to DNP3 to allow DNP3 time
synchronization. DNP3 delay measurement can have an adverse effect on time
synchronization accuracy, and should be avoided for TCP/IP.
Default Variation Obj N is the variation that the slave replies with when the master asks
for DNP Object type N variation 0. It is also the variation in which class events are
reported.
Table 9: Default variation options for supported DNP object types
DNP Obj N Default variation option
1
1 2
1
2 2
1
2
3
30 4
Table continues on next page
Variation description
Binary input
Binary input with status
Binary input event
Binary input event with time
32 bit analog input
16 bit analog input
32 bit analog input without flag
16 bit analog input without flag
Section 4
DNP3 parameters
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