GE Multilin D30 Line Distance Protection System 5-2115 SETTINGS 5.7 CONTROL ELEMENTS5d) BROKEN CONDUCTOR DETECTIONPATH: SETTINGS CONTROL ELEMENTS MONITORING ELEMENTS BROKEN CONDUCTOR 1(2)Two broken conductor detection elements are provided.The broken conductor function will detect a transmission line broken conductor condition or a single-pole breaker malfunc-tion condition through checking the phase current input signals and the I_2 / I_1 ratio. The intention of this function is todetect a single-phase broken conductor only. As such two-phase or three-phase broken conductors cannot be detected.To distinguish between single-phase disappearance and system disturbance in all three phases (such as load change,switching, etc.), the broken conductor element monitors the change in all three phase currents at the present instance andat four cycles previous. It also monitors changes in the I_2 / I_1 ratio, I_1 minimum, and I_1 maximum.The broken conductor function should not be used to respond to fault transients and single-pole tripping/reclosing condi-tions. Therefore, the time delay should be programmed to a sufficient length to ensure coordination with the breaker deadtime of the recloser function.• BROKEN CONDUCTOR 1 FUNCTION: This setting enables and disables the broken conductor function.• BROKEN CONDUCTOR 1 SOURCE: This setting selects a signal source used to provide three-phase current inputsto this function.• BROKEN CONDUCTOR 1 I2/I1 RATIO: This setting specifies the ratio of negative-sequence current to positive-sequence current. When one phase conductor is broken, the I_2 / I_1 ratio with a balanced remaining two phases is50%. So normally this setting should be set below 50% (for example, to 30%).• BROKEN CONDUCTOR 1 I1 MIN: This setting specifies the minimum positive-sequence current supervision level.Ensure this setting is programmed to a sufficient level to prevent I_2 / I_1 from erratic pickup due to a low I_1 signal.However, this setting should not be set too high, since the broken conductor condition cannot be detected under lightload conditions when I_1 is less than the value specified by this setting.• BROKEN CONDUCTOR 1 I1 MAX: This setting specifies the maximum I_1 level allowed for the broken conductorfunction to operate. When I_1 exceeds this setting, this it is considered a fault. This broken conductor function shouldnot respond to any fault conditions, so normally this setting is programmed to less than the maximum load current.• BROKEN CONDUCTOR 1 PKP DELAY: This setting specifies the pickup time delay for this function to operate afterassertion of the broken conductor pickup FlexLogic operand. BROKEN CONDUCTOR 1BROKEN CONDUCTOR 1FUNCTION: DisabledRange: Disabled, EnabledMESSAGE BROKEN CONDUCTOR 1SOURCE: SRC 1Range: SRC 1, SRC 2MESSAGE BROKEN CONDUCTOR 1I2/I1 RATIO: 20%Range: 20.0% to 100.0% in steps of 0.1%MESSAGE BROKEN CONDUCTOR 1I1 MIN: 0.10 puRange: 0.05 to 1.00 pu in steps of 0.01MESSAGE BROKEN CONDUCTOR 1I1 MAX: 1.50 puRange: 0.05 to 5.00 pu in steps of 0.01MESSAGE BROKEN CONDUCTOR 1PKP DELAY: 20.000 sRange: 0.000 to 65.535 s in steps of 0.001MESSAGE BROKEN CONDCT 1 BLK:OffRange: FlexLogic operandMESSAGE BROKEN CONDUCT 1TARGET: Self-resetRange: Self-reset, Latched, DisabledMESSAGE BROKEN CONDUCT 1EVENTS: DisabledRange: Disabled, Enabled
