Alstom MiCOM P546 - Page 352

P54x/EN OP/La4 Operation
(OP) 5-178 MiCOM P543, P544, P545 & P546
OP
In the case of the P544/P546, the two circuit breakers may be selectively controlled both
locally and remotely if relay contacts are assigned to allow a separate control trip contact
and a separate control close for each circuit breaker i.e. four output relay contacts.
+ve
Trip
0
Close
Local
Remote
Trip Close
ve
Protection
trip
Remote
control trip
Remote
control close
P0123ENa
Figure 115 Remote control of circuit breaker
A manual trip will be permitted provided that the circuit breaker is initially closed. Likewise, a
close command can only be issued if the circuit breaker is initially open. To confirm these
states it will be necessary to use the circuit breaker 52A and/or 52B contacts (the different
selection options are given from the CBx Status Input cell above). If no circuit breaker
auxiliary contacts are available then this cell should be set to None. Under these
circumstances no circuit breaker control (manual or auto) will be possible.
A circuit breaker close command (Close CB1 for CB1 or Close CB2 for CB2) will initiate
closing of the circuit breaker. The output contact, however, can be set to operate following a
user defined time delay (‘Man Close Delay’). This is designed to give personnel time to
retreat from the circuit breaker following the close command. This time delay applies to all
manual circuit breaker close commands.
The control close cycle can be cancelled at any time before the output contact operates by
any appropriate trip signal, or by activating DDB (443): Rst CB1 CloseDly for CB1 or by
DDB (1419): Rst CB2 CloseDly for CB2.
An Auto Close CB1 or Auto Close CB2 signal from the Auto close logic bypasses the Man
Close Delay time, and the CB1 Close or CB2 Close outputs operate immediately to close
the circuit breaker.
The length of the trip or close control pulse is set via the Trip Pulse Timeand Close Pulse
Time settings respectively. These should be set long enough to ensure the breaker has
completed its open or close cycle before the pulse has elapsed.
Note: The manual trip and close commands are found in the SYSTEM
DATA column and the hotkey menu.