ABB REC 561 User Manual page 506

ABB Network Partner AB
Version 1.0-00
November 1996
Function:
1 Application
2 Theory of operation
Event function
Basic
When using a Substation Automation system, events can be continu-
ously sent or polled from the terminal. These events can come from any
available signal in the terminal that is connected to the Event function
block. The Event function block can also handle double indication, that is
normally used to indicate positions of high-voltage apparatus. With this
Event function block in the REC 561 control terminal, data can be sent to
other control terminals over the LON bus.
The events can come from both internal logical signals and binary input
channels. The internal signals are time tagged in the main processing
module, while the binary input channels are time tagged directly on each
I/O module. The events are produced according to the set-event masks.
The event masks are treated commonly for both the LON and SPA chan-
nels. All events according to the event mask are stored in a buffer, which
contains up to 1000 events. If new events appear before the oldest event in
the buffer is read, the oldest event is overwritten and an overflow alarm
appears.
The outputs from the Event function block are formed by the reading of
status and events by the station MMI on either every input (single or dou-
ble input) or on the whole function block (16-bit word). The user-defined
name for each input is intended to be used by the station MMI.
The Event function block is executed with the same cyclicity as the fast
configurable logic. That means that the time-tagging resolution on the
events that are emerging from internal logical signals have corresponding
figures. The time tagging resolution on the events that are emerging from
binary input signals have a resolution of 1 ms.
Two special signals for event registration purposes are available in the ter-
minal, Terminal restarted and Event buffer overflow.
1MRK 580 140-XEN
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