GE c60 Instruction Manual

Also see for C60: Communications manual Communications guide Instruction manual Instruction manual Instruction manual

Contents

CHAPTER 5: SETTINGS CONTROL ELEMENTSC60 BREAKER PROTECTION SYSTEM – INSTRUCTION MANUAL 5-2535Scheme reset after reclosureWhen a reclose output signal is sent to close either breaker 1 or 2, the reset timer is started. If the reclosure sequence issuccessful (there is no initiating signal and the breakers are closed), the reset timer times out, returning the scheme to thereset state, with the shot counter set to 0, making it ready for a new reclose cycle.In two breaker schemes, if one breaker is in the out-of-service state and the other is closed at the end of the reset time, thescheme also resets. If at the end of the reset time at least one breaker, which is not in the out-of-service state, is open thescheme is sent to Lockout.The reset timer is stopped if the reclosure sequence is not successful: an initiating signal present or the scheme is inLockout state. The reset timer is also stopped if the breaker is manually closed or the scheme is otherwise reset fromlockout.LockoutWhen a reclose sequence starts by an initiate signal, the scheme moves into the reclose-in-progress state and starts theincomplete sequence timer. The setting of this timer determines the maximum time interval allowed for a single recloseshot. If a close breaker 1 or 2 signal is not present before this time expires, the scheme goes to “Lockout”.There are four other conditions that can take the scheme to the Lockout state, as follows:• Receipt of ‘Block’ input while in the reclose-in-progress state• The reclosing program logic — When a 3P Initiate is present and the autoreclose mode is either 1 Pole or 3Pole-A (3pole autoreclose for single pole faults only)• Initiation of the scheme when the count is at the maximum allowed• If at the end of the reset time at least one breaker, which is not in the out-of-service state, is open the scheme is sentto Lockout. The scheme is also sent to Lockout if one breaker fails to reclose and the setting AR BKR FAIL OPTION is setto “Lockout”.Once the Lockout state is set, it is latched until one or more of the following occurs:• The scheme is intentionally reset from Lockout, employing the Reset setting of the Autorecloser• The Breaker(s) is(are) manually closed from panel switch, SCADA, or other remote control through the AR BRK MANCLOSE setting;• 10 seconds after breaker control detects that breaker(s) were closedBreaker open before faultA logic circuit is provided that inhibits the close breaker 1 and close breaker 2 outputs if a reclose initiate (RIP) indicator isnot present within 30 ms of the Breaker Any Phase Open input. This feature is intended to prevent reclosing if one of thebreakers was open in advance of a reclose initiate input to the recloser. This logic circuit resets when the breaker is closed.Transfer reclose when breaker is blocked• When the reclosing sequence 1-2 is selected and Breaker 1 is blocked (AR BKR1 BLK operand is set) the reclose signalcan be transferred direct to the Breaker 2 if AR TRANSFER 1 TO 2 is set to “Yes.” If set to “No”, the scheme is sent toLockout by the incomplete sequence timer.• When the reclosing sequence 2-1 is selected and Breaker 2 is blocked (AR BKR2 BLK operand is set) the reclose signalcan be transferred direct to the Breaker 1 if AR TRANSFER 2 TO 1 is set to “Yes.” If set to “No” the scheme is sent toLockout by the incomplete sequence timer.Force three-pole trippingThe reclosing scheme contains logic that is used to signal trip logic that three-pole tripping is required for certainconditions. This signal is activated by any of the following:• Autoreclose scheme is paused after it was initiated• Autoreclose scheme is in the lockout state• Autoreclose mode is programmed for three-pole operation