Features

•Integrated three-phase differential relay, three-phase overcurrent relay and multi-configurable earth-fault relay
•Alarm channels activated by normally open or normally closed contact
•Stabilized differential relay module providing winding short-circuit and interturn fault protection for two-winding power transformers and generator-transformer units, and interwinding short-circuit protection for generators
•Earth-fault relay module providing protection for transformer HV and LV side according to the principle selected: stabilized differential current principle, high-impedance principle, residual current principle or neutral current principle
•Three-stage overcurrent module providing protection for power transformers and generators and two-stage back-up earth-fault protection
•Short operate time even at partial saturation of the current transformers
•Operation characteristic of differential relay module easily adapted for different applications
•Stabilized against unwanted operations at faults occurring outside the protected area and at transformer inrush currents
•Second harmonic restraint for prevention of unwanted relay operations at transformer inrush currents
•Fifth harmonic restraint for prevention of unwanted relay operations at transformer overexcitation. The fifth harmonic restraint can be aborted if the ratio of the fifth harmonic and the basic frequency component rises too high at dangerous overvoltages
•Wide CT ratio correction range: accurate correction through digital setting
•No interposing current transformers needed for the protection of two-winding power transformers: numerical vector group matching on HV and LV side
•Four heavy-duty output relays for circuit breaker tripping and five output relays for signalling
•Five programmable external control inputs intended for alarm and trip signals from gas relays, oil temperature sensors and other sensors of transformer auxiliary devices
•Integrated circuit-breaker failure protection with adjustable operate time
•Differential relay and earth-fault relay modules provided with integrated disturbance recorder functions for analog and digital signals: signals to be used for triggering selectable
•Sensitive phase current and phase angle displays facilitate checking of energizing circuit connections and vector group matchings
•High immunity to electrical and electromagnetic interference allows the relay to be used in severe environments
•High availability and system reliability due to continuous supervision of hardware and software
•Powerful software supports relay parameterization and reading of measured and recorded values and event data
•Member of the SPACOM product family and ABB’s Distribution Automation system
•CE marking according to the EC directive for EMC