RCS-985T Transformer Protection Disagreement Relay Restricted earth fault protection and Thermal overload protection

The RCS-985T is a high-performance transformer protection intended for the applications to startup/standby transformers and auxiliary transformers in power plants. This full-integrated transformer protection integrates protection, control and monitoring functions to provide users with a comprehensive, reliable and cost-effective solution. The RCS-985T is fully compatible with IEC 61850 communication with an additional communication unit.


Protection and control

Variable slope percentage differential protection (7 sides maximum). (87T)
Unrestrained differential protection. (50/87UT)
Restricted earth fault protection(zero-sequence differential current protection) at HV side. (64REF/87G)
Restricted earth fault protection(zero-sequence differential current protection) at LV side A. (64REF/87G)
Restricted earth fault protection(zero-sequence differential current protection) at LV side B. (64REF/87G)
Voltage controlled overcurrent protection at HV side. (50P/51P)
Voltage controlled directional zero-sequence overcurrent protection at HV side. (50N/51N/67N)

Gap zero-sequence overvoltage protection at HV side. (59N)
Gap zero-sequence overcurrent protection at HV side.(50N/51N)
Voltage controlled overcurrent protection of branches at LV side. (50P/51P)
Pole disagreement protection. (62PD)
Over excitation protection. (24)
Thermal overload protection. (49)
Cooling initiation function. (49)
On-load tap change (OLTC) blocking function during overload. (49)
Zero-sequence voltage alarm of branches at LV side. (59G)
VT circuit failure supervision.
CT circuit failure supervision.
CT saturation detection.

Monitoring and metering

Self diagnostic.
DC power monitoring and alarming.
Event Recorder including 256 statuses change of binary input reports, 64 self-supervision reports and 64 operating reports.
Disturbance recorder including 64 fault reports, and 8 waveforms. The maximal record time is up to 15s for single fault waveform. (The file format of disturbance recorder is compatible with international COMTRADE file.)
GPS clock synchronization: PPS (pulse per second)

Communication

2 RS-485 communication rear ports conform to IEC 60870-5-103 protocol or Modbus protocol.
3 optional Ethernet ports conform to IEC 60870-5-103 protocol over TCP/IP