GE Multilin L60, Instruction Manual

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GE Multilin L60 Line Phase Comparison System 5-253
5 SETTINGS 5.6 CONTROL ELEMENTS
5
• TRIP 3-POLE INPUT-1 to TRIP 3-POLE INPUT-6 : These settings are used to select an operand representing a fault
condition that is not desired to initiate a single pole operation (for example, phase undervoltage). Use a FlexLogic OR-
gate if more than six inputs are required.
• TRIP 1-POLE INPUT-1 to TRIP 1-POLE INPUT-6 : These settings are used to select an operand representing a fault
condition that is desired to initiate a single pole trip-and-reclose if the fault is single phase to ground (for example, dis-
tance zone 1). Use a FlexLogic OR-gate if more than six inputs are required. The inputs do not have to be phase-spe-
cific as the phase selector determines the fault type.
The
AR FORCE 3-P TRIP
operand is asserted by the autorecloser 1.5 cycles after single-pole reclosing is initiated. This
operand calls for a three-pole trip if any protection element configured under
TRIP 1-POLE INPUT
remains picked-up. The
open pole detector provides blocking inputs to distance elements, and therefore the latter will reset immediately after
the
TRIP 1-POLE
operand is asserted. For other protection elements used in single-pole tripping, the user must ensure
they will reset immediately after tripping, otherwise the fact that they are still picked up will be detected as an evolving
fault and the relay will trip three-poles. For example, if high-set phase instantaneous overcurrent is used (
TRIP 1-POLE
INPUT X:
“
PHASE IOC1 OP
”), then
OPEN POLE OP

A
shall be used for blocking phase A of the instantaneous overcur-
rent element. In this way, after tripping phase A, the phase a instantaneous overcurrent element is forced to reset.
Phases B and C are still operational and can detect an evolving fault as soon as 8 ms after tripping phase A. Neutral
and negative-sequence instantaneous overcurrent elements shall be blocked from the
OPEN POLE BLK N
operand
unless the pickup setting is high enough to prevent pickup during single-pole reclosing.
• TRIP RECLOSE INPUT-1 to TRIP RECLOSE INPUT-6 : These settings select an operand representing a fault condi-
tion that is desired to initiate three pole reclosing (for example, phase distance zone 1). Use a FlexLogic OR-gate if
more than six inputs are required. These inputs also include the
TRIP 1-POLE INPUT-1
to
TRIP 1-POLE INPUT-6
values,
which are intended to initiate three-pole reclosing in situations where single-pole tripping commands are changed to
three-pole tripping commands. This can happen in cases where the phase selector identifies a multi-phase fault or the
AR FORCE 3P TRIP
command is present.
• TRIP SEAL-IN DELAY : This setting specifies the minimum time that trip command signals are maintained to provide
sufficient time to open the breaker poles. If a value of “0” is specified, then the output signal is reset once the protection
elements initiating the trip are reset. If a value other than “0” is specified, then the protection elements must reset and
the timer initiated at the first trip command must expire.
• TRIP RESET : This setting selects the option to reset the trip latches. If “Pole Curr OR Custom” is chosen, then the
OPEN POLE CURRENT PKP
setting should be programmed accordingly. If “CBaux OR Custom” is chosen, then the break-
ers should be set appropriately. Both the “Current” and “CBaux” options can be complimented by custom conditions
using the
BKR Φ A OPEN
,
BKR Φ B OPEN
, and
BKR Φ C OPEN
settings indicated below. Alternately, a purely custom condi-
tion can be applied to reset trip output latches.
• START TMR Z2PH Inp1 and START TMR Z2PH Inp2 : These settings select an operand that will start the phase dis-
tance zone 2 timer to avoid a trip delay if the fault evolves from one type to another type (for example, from a single-
line–to-ground fault to a multi-phase fault) or from one zone of protection to another zone of protection (for example,
from zone 3 to zone 2). For instance, the
GND DIST Z2 PKP
FlexLogic operand or the
PH DIST Z3 PKP
FlexLogic oper-
and could be assigned to either of these settings. Use a FlexLogic OR-gate if more than two inputs are required. Refer
to phase distance logic diagrams for additional information.
• START TMR Z2GR Inp1 and START TMR Z2GR Inp2 : These settings select an operand that starts the ground dis-
tance zone 2 timer to avoid a trip delay if the fault evolves from one zone of protection to another zone of protection (for
example, from zone 3 to zone 2). For instance, the
GND DIST Z3 PKP
FlexLogic operand could be assigned to these
settings. Use a FlexLogic OR-gate if more than two inputs are required. See the ground distance logic diagrams for
additional information.
• PH SELECT RST DELAY : This setting specifies the reset delay of the Phase Selector element outputs after system
disturbance occurs. This delay has to be long enough to allow elements assigned to cause single-pole tripping to oper-
ate. If, for example, it is intended that distance zone 2 with a time delay of 0.5 seconds causes a single-pole trip, then
this setting has to be at least 0.6 seconds. See the
Phase Selection section in the Theory of Operation chapter for
more information.
• TRIP FORCE 3-POLE : Selects an operand that forces an input selected for single pole operation to produce a three-
pole operation. The
AR DISABLED
FlexLogic operand is the recommended value for this setting. Power system config-
urations or conditions that require such operations can be considered as well.