Alstom MiCOM P846, Technical Manual

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Operation P846/EN OP/D
MiCOM P846
(OP) 5-19
2.7 Circuit breaker control
OP
r control of a single circuit breaker:
relay menu or hotkeys
. Where this feature is not required the
same output contact(s) can be used for both protection and remote tripping.
The relay includes the following options fo
•
Local tripping and closing, via the
•
Local tripping and closing, via relay opto-isolated inputs
•
Remote tripping and closing, using the relay communications
It is recommended that separate relay output contacts are allocated for remote circuit
breaker control and protection tripping. This enables the control outputs to be selected via a
local/remote selector switch as shown in Figure 13
+ve
Trip
0
Protection
trip
Close
Local
Remote
Trip Close
–ve
Remote
ENa
control trip
Remote
control close
P0123
Figure 13: Remo rol of circuit
A manual trip will be permitted pro cuit bre
close command can only be issued if the CB is initially op it will
be necessary to use the breaker 52A and/or 52B contacts (the different selection options are
th Status Input’). If no CB auxiliary contacts are available then this cell
aker following the close command. This time delay will apply to all
et long enough to ensure the breaker
has completed its open or close cycle before the pulse has elapsed.
Note that the manual trip and close commands are found in the SYSTEM DATA
column and the hotkey menu.
If an attempt to close the breaker is being made, and a protection trip signal is generated,
the protection trip command overrides the close command.
te cont breaker
vided that the cir aker is initially closed. Likewise, a
en. To confirm these states
given from e ‘CB
should be set to None. Under these circumstances no CB control (manual or auto) will be
possible.
Once a CB Close command is initiated the output contact can be set to operate following a
user defined time delay (‘Man. Close Delay’). This would give personnel time to move safely
away from the circuit bre
manual CB Close commands.
The length of the trip or close control pulse can be set via the ‘Trip Pulse Time’ and ‘Close
Pulse Time’ settings respectively. These should be s