ABB REC 561 User Manual page 316

ABB Network Partner AB
Version 1.0-00
Apparatus control
If this interlocking information needs additional event blocks for sending,
the first bit of all the extra blocks is a reserve acknowledgement signal to
acknowledge any bays, see Fig. 18.
These steps can be defined for the complete execution:
• The command execution bay receives a request for operation, for
example by a selection from MMI.
• If the bay is reserved the command is cancelled.
• If other bays should be reserved, the reserve request bit is set in the
event function block.
• The request information is broadcasted to all other bays.
• The receiving bays put the data to the command function blocks in
the different bays.
• The bays that must be reserved, read the request from the command
function block, block all commands in the own bay, evaluate the
apparatus positions, and set the interlocking information and the
reserve acknowledgement on the event function block.
• The response is broadcasted to all other bays.
• The other bays configured to read this message put the data to the
command function blocks.
• The command executing bay receives reserve acknowledgement sig-
nals from all the bays that were requested. If one or several bays do
not respond within a predefined time, the command is cancelled.
• When all reserve acknowledgement signals are received, the inter-
locking condition is evaluated. If the command is allowed, it will be
performed.
• When the command is executed, the reserve request bit is reset on all
event function blocks and broadcasted in the same way as the reserve
request.
• The reset reserve request bit is interpreted as a release in the bay that
was reserved. So the bay is free, and the reserve acknowledgement
bit is reset on the event function block and broadcasted back.
• The command executing bay waits until all reserve acknowledge-
ment signals are reset. When this is done, the bay is ready for a new
command.
Example:
Fig. 18 illustrates the above described step-by-step command execution
and bay-to-bay communication.
The example station is a double busbar with only two lines and one bus
coupler. The bus coupler also handles the busbar earthing switches.
In this station, Line 1 and Line 2 need information from the bus coupler
and the bus coupler need information from Line 1 and Line 2.
1MRK 580 150-XEN
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