Areva MiCOM P441, Technical Manual

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Application Notes P44x/EN AP/E33
MiCOM P441/P442 & P444 Page 137/220
A/R 1p in Prog
The DDB A/R 1P in Prog if assigned to an opto input in the PSL and when energized, will
block the internal DEF as an external single pole AR cycle is in progress.
A/R 3p in Prog
The DDB A/R 3P in Prog if assigned to an opto input in the PSL and when energized, will
inform the P44X about the presence of an external 3P cycle.That data could be used in case
of evolving fault
A/R Close
The DDB A/R Close if assigned to an opto input in the PSL and when energized, could be
linked with the internal check sync condition to control the external CB closing command.
A/R Reclaim
The DDB A/R Reclaim if assigned to an opto input in the PSL and when energized, will
inform the protection about an external reclaim time in progress; and will initiate the internal
TOR logic. (That information extension logic, by using a dedicated PSL could be used also
in Z1x.
BAR
Block Autoreclose (via Opto Input or PSL) – see Figure 80.
The DDB: BAR input will block the autoreclose and lockout the AR if in progress. If a single
pole cycle is in progress a three pole trip and lockout will be issued. It can be used when
protection operation without autoreclose is required. A typical example is on a transformer
feeder, where autoreclosing may be initiated from the feeder protection but blocked from the
transformer protection. Similarly, where a circuit breaker low gas pressure or loss of vacuum
alarm occurs during the dead time, autoreclosure, should be blocked – and BAR can be
used to realise that blocking logic.
Ext Chk Synch OK
External Check Synchroniser Used (via Opto Input) – Dedicated PSL required to be
configured.
If an opto input is assigned in the PSL (DDB: Ext Chk Synch OK), the AR close command
will be controlled by an external check synchronism device. The input is energised when the
Check Sync conditions are verified.
CB Healthy
(via Opto Input)
The majority of circuit breakers are only capable of providing one trip-close-trip cycle. It is
necessary to re-establish sufficient energy in the circuit breaker before the CB can be
reclosed. The DDB: CB Healthy input is used to ensure that there is sufficient energy
available to close and trip the CB before initiating a CB close command. If on completion of
the dead time, sufficient energy is not detected by the relay within a period given by the AR
Inhibit Wind window, lockout will result and the CB will remain open (AR BAR Picks up –
see Figure 79) If the CB energy becomes healthy during the time window, autoreclosure will
occur. This check can be disabled by not allocating an opto input. In this case, the DDB cell
“CB Healthy” is considered invariant for the logic of the relay. This will mean that the signal
is always high within the relay (when the logic required a high level) and at 0, if low level is
requested. It is an invariant status for the firmware (Same logic is applied for every optional
opto – if not linked in the PSL these cells are managed as invariant data for internal logic).