Transmission signal control board PFSK152 3BSE018877R2

Transmission signal control board PFSK152 3BSE018877R2

Transmission signal control board PFSK152 3BSE018877R2

• Setting parameter OpenCTEnable enables and disables this feature.
• • Setting parameter OCTBlockEnenables and disables the blocking of differential function once an open CT is detected. When OCTBlockEn is set to OFF, only an alarm signal is issued.
• • Setting parameter tOCTAlarmDelay defines the time delay after which the alarm signal is given.
• • Setting parameter tOCTResetDelay defines the time delay after which the open CT condition resets once the defective CT circuits have been repaired.
• • Once the open CT condition has been detected, all the differential protection functions are blocked except the unrestrained (instantaneous) differential protection. However, there is no guarantee that an unwanted disconnection of the protected circuit can always be prevented.
• • For applications where the currents from two CTs are summated and sent over LDCM, the output OPENCT must be connected to CTFAIL on LDLPSCH logic in order for the Open CT detection to operate properly. Observe that summation of currents shall be avoided where possible. The outputs of the open CT conditions are OPENCT and OPENCTAL.
• • OPENCT: Open CT detected • OPENCTAL: Alarm issued after the setting delay Outputs (positive integer) for information on the local HMI:
• • OPENCTIN: Open CT in CT group inputs (1 for input 1 and 2 for input 2)
• • OPENCTPH: Open CT with phase information (1 for phase L1, 2 for phase L2, 3 for phase L3)