11. Autoreclosing Reclaim Time is exceeded and Autorecloser is set to Ready state waiting for next
request.
Auto-reclosing sequence from Trip with two shot, high speed succeeds
The Scheme for autoreclosing starter and shots is the same than in the previous examples with same
settings and signals. In this example fault is cleared by the high speed autoreclosing.
Figure. 5.5.4. - 130. Settings for earth fault reclosing with two shots.
This type of sequence represents 75-85% of all the faults in the medium voltage overhead line network.
Figure. 5.5.4. - 131. Signal status graph of the transient earth fault autoreclosing cycle.
1. Earth fault is found in the protected line which causes directional earth fault protection I0Dir> to
start and calculate the operating time for the trip.
2. I0Dir> trips and gives open command to the breaker open coil. Autoreclosing REQ2 is initiated
and AR running, AR2 Requested and Shot1 Running signals are activated.
3. Circuit breaker is opened and I0Dir> Trip signal is released and simultaneously REQ2 signal for
autorecloser is released. Recloser starts to calculate the Shot1 Dead Time for closing the
breaker.
4. Dead Time for Shot1 is exceeded and autorecloser sends close request for the Object breaker,
the close conditions are met and the breaker close command is sent to breaker close coil.
AQ-F255
Instruction manual
Version: 2.00
© Arcteq Relays Ltd
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