GE Multilin D60 Line Distance Protection System 5-2615 SETTINGS 5.7 CONTROL ELEMENTS5The “rest” position (0, 0, 0) does not generate an action and is intended for situations when the device generating thethree-bit control word is having a problem. When SELECTOR 1 3BIT MODE is “Time-out”, the pre-selected position isapplied in SELECTOR 1 TIME-OUT seconds after the last activity of the three-bit input. When SELECTOR 1 3BIT MODE is“Acknowledge”, the pre-selected position is applied on the rising edge of the SELECTOR 1 3BIT ACK acknowledginginput.The stepping up control input (SELECTOR 1 STEP-UP) and the three-bit control inputs (SELECTOR 1 3BIT A0 through A2)lock-out mutually: once the stepping up sequence is initiated, the three-bit control input is inactive; once the three-bitcontrol sequence is initiated, the stepping up input is inactive.• SELECTOR 1 3BIT MODE: This setting defines the selector mode of operation. When set to “Time-out”, the selectorchanges its position after a pre-defined period of inactivity at the control input. The change is automatic and does notrequire explicit confirmation to change the selector position. When set to “Acknowledge”, the selector changes its posi-tion only after confirmation via a separate acknowledging signal. If the acknowledging signal does not appear within apre-defined period of time, the selector rejects the change and an alarm established by invoking the SELECTOR BITALARM FlexLogic operand for 3 seconds.• SELECTOR 1 3BIT ACK: This setting specifies an acknowledging input for the three-bit control input. The pre-selected position is applied on the rising edge of the assigned FlexLogic operand. This setting is active only under the“Acknowledge” mode of operation. The acknowledging signal must appear within the time defined by the SELECTORTIME-OUT setting after the last activity of the three-bit control inputs. Note that the stepping up control input and three-bit control input have independent acknowledging signals (SELECTOR 1 ACK and SELECTOR 1 3BIT ACK, accordingly).• SELECTOR 1 POWER-UP MODE: This setting specifies the element behavior on power up of the relay.When set to “Restore”, the last position of the selector (stored in the non-volatile memory) is restored after powering upthe relay. If the position restored from memory is out of range, position 0 (no output operand selected) is applied andan alarm is set (SELECTOR 1 PWR ALARM ).When set to “Synchronize” selector switch acts as follows. For two power cycles, the selector applies position 0 to theswitch and activates SELECTOR 1 PWR ALARM . After two power cycles expire, the selector synchronizes to the positiondictated by the three-bit control input. This operation does not wait for time-out or the acknowledging input. When thesynchronization attempt is unsuccessful (that is, the three-bit input is not available (0,0,0) or out of range) then theselector switch output is set to position 0 (no output operand selected) and an alarm is established ( SELECTOR 1 PWRALARM ).The operation of “Synch/Restore” mode is similar to the “Synchronize” mode. The only difference is that after anunsuccessful synchronization attempt, the switch will attempt to restore the position stored in the relay memory. The“Synch/Restore” mode is useful for applications where the selector switch is employed to change the setting group inredundant (two relay) protection schemes.• SELECTOR 1 EVENTS: If enabled, the following events are logged:EVENT NAME DESCRIPTIONSELECTOR 1 POS Z Selector 1 changed its position to Z.SELECTOR 1 STP ALARM The selector position pre-selected via the stepping up control input has not beenconfirmed before the time out.SELECTOR 1 BIT ALARM The selector position pre-selected via the three-bit control input has not been confirmedbefore the time out.
