Event Handling; Event Buffer Overflow; Dnp Counters And Frozen Counters; Collision Avoidance And Detection - ABB REF610 Technical Reference Manual

REF610 REF610
114
Feeder Protection Relay
Technical Reference Manual - ANSI Version

Event handling

The maximum capacity of the DNP event buffer is 100 events. When unsolicited
reporting has been enabled (SPA parameter 503V24), the event reporting uses the
following SPA parameters, called send throttle parameters:
Class 1 Event delay
503V18
Class 1 Event count
503V19
Class 2 Event delay
503V20
Class 2 Event count
503V21
Class 3 Event delay
503V22
Class 3 Event count
503V23
Example:
(class 1)
The events are reported when the event delay (SPA parameter 503V18) has
elapsed or the defined amount of events (SPA parameter 503V19) are
generated for class 1.
If send throttles are not wanted, the event delay should be set to 0 and the
event count to 1. In this case, the class events are sent to the host immediately
as they occur.

Event buffer overflow

DNP 3.0 event buffer overflow is indicated with the internal target IIN2.3, as
defined by the standard. IIN2.3 can also indicate event buffer overflow in the
internal communication between the DNP3.0 module and the main CPU module of
the relay. In this case, the relay automatically activates and resets the IIN2.3 bit.
As events have been lost in both cases, the DNP 3.0 master should perform an
integrity scan after the IIN2.3 bit has been reset.

DNP counters and frozen counters

DNP counters in use have a corresponding frozen counter. The frozen counters in
object group 21 have the same DNP point index as the ordinary DNP counters.
Further, frozen counters can only be read as static objects, and frozen counter events
(object group 23) are not supported.

Collision avoidance and detection

The relay supports both collision avoidance and detection. Collision detection can
be enabled or disabled with SPA parameter 503V235. Collision avoidance occurs
before message transmission. When preparing to transmit and the link is busy, the
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