Auto-Reclose and Check Synchronising
General Information
- Description
Automatic circuit reclosing is extensively applied to overhead line circuits where a high percentage of faults that occur are transient in nature. Automatic reclosing of the circuit breaker attempts to minimise the loss of supply to the customer and reduce the need for manual intervention.
Check synchronising ensures that a circuit breaker can only be closed when the voltages and frequency of the power system on each side of that circuit breaker are within acceptable limits.
Our Portfolio (3)
- Description
- Function overview
- Features
7SR224 series relays include for directional control of three phase overcurrent and earth fault functionality and typically installed as an integral controller for a pole mounted recloser. The controller offers an integrated auto-reclose solution for use on OHL feeders.
The relay functionality allows highly flexible settings for current and time grading making it compatible with all types of overcurrent protections.
Relays have four current and four voltage inputs and are housed in E10 cases.
Integrated logic is provided to allow the optimal configuration of relay functionality with the relays analogue inputs and binary input/output circuits.
Protection, instrumentation and metering functionality is accessible via data comms channel(s). A front USB port for local PC connection and rear electrical RS485 port for remote connection are provided as standard, additional ports are available as options.
Protection Functions
- Undercurrent (37)
- Broken Conductor (46BC)
- Negative Phase Sequence Overcurrent (46NPS)
- Thermal Overload (49)
- Overcurrent (50, 51)
- Earth Fault (50G, 50SEF, 51G, 51SEF)
- High Impedance REF (64H)
- Under/Over Voltage (27/59)
- Negative Phase Sequence Voltage (47)
- Voltage Controlled Overcurrent (51V)
- Neutral Voltage Displacement (59N)
- Directional Control of Overcurrent & Earth Fault (67)
Supervision Functions
- CT Supervision (60CTS)
- Trip & Close Circuit Supervision (74T/CCS)
- VT Supervision (60VTS)
- Inrush Detector (81HBL2)
- Circuit Breaker Fail (50BF)
Control Functions
- Auto Reclose (79)
Monitoring Functions
- Primary/Secondary Current Phases and Earth Direction
- Primary/Secondary Line and Phase Voltages
- Apparent Power and Power Factor
- Real and Reactive Power
- W Hr & VAr Hr Forward and Reverse
- Historical Demand Record
- Positive Phase Sequence (PPS) Voltage & Current
- Negative Phase Sequence (NPS) Voltage & Current
- Zero Phase Sequence (ZPS) Voltage
- Cold Load Settings
- Eight Settings Groups
- Password Protection - 2 levels
- User Programmable Logic
- Self Monitoring
- Circuit Breaker Trip Counter and Timer
- Fault, event and waveform records