Siemens 7SR224 Description & Operation page 44

(1) Description of Operation 7SR224
Notes on the 'Lockout' State
The Lockout state can be reached for a number of reasons. Lockout will occur for the following: -
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At the end of the 79 Sequence Fail Timer.
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At the end of the Reclaim timer if the CB is in the open position.
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A protection operates during the final Reclaim time.
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If a Close Pulse is given and the CB fails to close.
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The 79 Lockout binary input is active.
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At the end of the 79 Reclose Blocked Delay due to presence of a persistent Block signal.
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When the 79 Elem HS Trips to Lockout count is reached.
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When the 79 Elem Delayed Trips to Lockout count is reached.
Once lockout has occurred, an alarm (79 Lockout) is issued and all further Close commands, except
manual close, are inhibited.
If the Lockout command is received while a Manual Close operation is in progress, the feature is
immediately locked-out.
Once the Lockout condition has been reached, it will be maintained until reset. The following will reset
lockout: -
•
By a Manual Close command, from fascia, comms or Close CB binary input.
•
By a 79 Reset Lockout binary input, provided there is no signal present that will cause
Lockout.
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At the end of the 79 Minimum LO Delay time setting if 79 Reset LO by Timer is selected
to ENABLED, provided there is no signal present which will cause Lockout.
•
Where Lockout was entered by an A/R Out signal during an Autoreclose sequence then a
79 In signal must be received before Lockout can reset.
•
By the CB Closed binary input, provided there is no signal present which will cause
Lockout.
The Lockout condition has a delayed drop-off of 2s.
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