The PCS-9691 relay is a protection, control and monitoring unit for various applications (such as overhead line, underground cable, transformer and capacitor etc.) on solidly grounded, impedance grounded, Peterson coil grounded and ungrounded system. The PCS-9691 features a high performance functional library, programmable logic, configurable I/O and integrated frequency-tracking.
The PCS-9691 is designed based on advanced multiprocessor platform, fully complying with IEC 61850 station bus, supporting IEC 61850-8-1 MMS.
Functons:
Protection
Six-stage phase overcurrent protection(50/51P)
Four-stage directional phase overcurrent protection (67P)
Six-stage neutral/ground overcurrent protection(50/51N, 50/51G)
Four-stage directional neutral/ground overcurrent protection(67N/G)
Two-stage negative-sequence overcurrent protection (46)
Thermal overload protection for alarm/trip (49)
Broken conduct detection (46BC)
Breaker failure element (50BF)
Dead zone protection (50DZ)
Undercurrent protection (37)
Restricted earth fault protection (64REF)
Two-stage phase-ground or phase-phase undervoltage protection (27)
Two-stage phase-ground or phase-phase overvoltage protection (59)
Two-stage ground overvoltage protection (59G)
One-stage negative sequence overvoltage protection (47)
Four-stage under-frequency protection (81U)
Over-frequency protection (81O)
Frequency rate-of-change protection (81R)
Directional power protection (32)
Four-shot three-pole auto-reclosing (79)
Synchronism check for manual closing and auto- reclosing (25)
Switch onto fault logic (SOTF)
Cold load pickup logic (CLP)
Mechanical protection (MR)
Fault location (FL)
Voltage and current drift auto adjustment
Control
Remote/Local control
Lock/unlock logic
Face plate control button
Monitoring
Tripping circuit supervision (TCS)
Voltage transformer supervision (VTS)
Current transformer supervision (CTS)
Circuit breaker status monitoring
Self supervision
Communication
Up to two 100Base-FX ports with IEC 61850-8-1 MMS for non-time-critical message, IEC 60870-5-103 over TCP/IP or DNP 3.0
One RS-485 rear port with IEC 60870-5-103 or Modbus
One RS-485 rear port for clock synchronization
1 faceplate RJ45 port for testing and setting
Clock synchronization via pulse per second, IRIG-B and SNTP
Features:
High-setting and low-setting elements are provided for Restricted Earth Fault protection (REF). CT saturation detection element is integrated for the blocking of low-setting REF. The CT ratio compensation is provided to eliminate the unbalance due to CT ratio.
Six-stage over- & under- frequency protections and four-stage change-of-frequency (df/dt) are integrated to implement load shedding and other control schemes. The over- & under- frequency protection is controlled by voltage element to avoid the mal-operation due to short-circuit faults.
Cold load pickup logic is integrated to automatically increase the setting of phase overcurrent and zero sequence overcurrent protections to improve the adaptability for various loads.
Fault locator function is integrated for the post-fault checking and maintenance.
Dead zone protection is integrated to clear the faults between the CT coil and the circuit breaker.
Directional power element is provided for the reverse power protection or forward power protection.
Thermal model based on IEC60255-8 standard is integrated for thermal overload protection. The fundamental current and 2nd to 7th harmonics are utilized for thermal accumulation.
Broken conduct protection can be automatically blocked for a very short time to avoid the mal-operation due to the circuit breaker switching.
Up to six stages of phase overcurrent protection are provided for various applications. Four stages can be controlled by directional element, harmonic blocking element and voltage element (phase-phase undervoltage or negative sequence overvoltage)
Up to six stages of neutral/ground(zero sequence) overcurrent protection are integrated. Four stages can be controlled by directional element and harmonic blocking element.
12 IDMT curves are integrated: five IEC curves (short time inverse, standard inverse, very inverse, extremely inverse, long time inverse), six IEEE/ANSI curves (short time inverse, moderately inverse, inverse, very inverse, extremely inverse, long time inverse) and one self-defined curve.
Self-adaptive polarized voltage is employed for directional element to avoid the mal-operation due to the close-in severe three-phase faults. The memorized voltage or measured voltage is automatically selected according to different scenario.
Independent phase overcurrent element and zero sequence overcurrent element are employed for the Switch-Onto-Fault (SOTF) logic to achieve the high-speed tripping.
Phase-ground voltage or phase-phase voltage can be selected for overvoltage and undervoltage protections. Selective 1-phase (‘OR’ logic) and 3-phase (‘AND’ logic) modes are supported.
Up to 13th harmonics are measured for power quality monitoring.
Four self-definable buttons are provided in the face-plate for easy control and maintenance. The button can be set as the remote/local, lock/unlock, open/close for the circuit breaker control.
Powerful disturbance recording function is integrated in the relay for after-fault analysis. Up to 64 disturbance reports can be stored in non-volatile memory. Each report includes 5-cycle pre-fault waveform and 100-cycle to 416-cycle post-fault waveform.