Areva MiCOM P441, Technical Manual

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P44x/EN AP/E33 Application Notes
Page 128/220 MiCOM P441/P442 & P444
4.5.3 Auto-reclose logic operating sequence
An autoreclose cycle is internally initiated by operation of a protective element (could be
started by an internal trip or external trip), provided the circuit breaker is closed at the instant
of protection operation. The appropriate dead timer for the shot is started (Dead Time 1, 2, 3
or 4; noting that separate dead times are provided for the first high speed shot of single pole
(1P), and three pole (3P), reclosure). At the end of the dead time, a CB close command of
set duration = Close Pulse is given, (See Figure 76 with AR Close logic) provided system
conditions are suitable. The conditions to be met for closing are that the system voltages
satisfy the internal check synchronism criteria (set in the System Checks section of the relay
menu – and in a dedicated PSL (needs to be created by user – see section 4.2.8), and that
the circuit breaker closing spring, or other energy source, is fully charged indicated from the
DDB: CB Healthy input (Optional application / See Figure 78 and Figure 82 AR inputs).
When the CB has closed the reclaim time (Reclaim Time) starts (See Figure 76 with AR
Close logic). If the circuit breaker has been not retrip, the autoreclose logic is reset at the
end of the reclaim time. The autorecloser is ready again to restart from the first shot a new
cycle again (for future faults). If the protection retrips during the reclaim time, the relay either
advances to the next shot in the programmed autoreclose cycle, or, if all programmed
reclose attempts have been made, goes to lockout.
P0555ENa
Dead Time_1P or
Dead Time_3P
Close Pulse
AR_Trip_3ph
Reclaim Time
Trip_1P or Trip_3P
FIGURE 76 - AR CYCLE – GENERAL DESCRIPTION
P0556ENa
Dead Time_1P
Dead Time_3P
Close Pulse
AR_Trip_3ph
AR_Trip_3ph and Reclaim
Time stop with next Trip
Reclaim Time
Trip_1P or Trip_3P
FIGURE 77 - SUCCESSIVE AR CYCLE – SECOND TRIP ORDER BEFORE RECLAIM TIME IS ISSUED