ABB REM543CG214AAA A Machine Terminal

The ABB REM543CG214AAA A is a numerical machine terminal from the REM 543 series, designed for the protection, control, and monitoring of generator-transformer units in power plants and industrial facilities. As an intelligent electronic device (IED), it integrates comprehensive protection functions with advanced communication capabilities, ensuring reliable and selective fault clearance while maximizing equipment availability. This model variant, REM543CG214AAA A, features a specific hardware and software configuration tailored for demanding generator protection applications.

Generator-Transformer Protection Functions

The REM543CG214AAA A provides a complete suite of protection elements essential for safeguarding generators and step-up transformers. Core protection functions include:

• Differential protection (87G, 87T): High-impedance or biased differential with second and fifth harmonic blocking to prevent maloperation during transformer inrush and generator overexcitation.

• Stator earth fault protection: 95% and 100% coverage using third-harmonic voltage and injection methods, ensuring detection of earth faults anywhere in the stator winding.

• Rotor earth fault protection: One- or two-stage protection with AC or DC injection, detecting ground faults in the field winding.

• Overexcitation (V/Hz): Inverse-time characteristic with definite time limit, protecting the generator and transformer from excessive flux density.

• Overcurrent (50/51): Three-phase and earth fault overcurrent with directional options (67/67N).

• Negative sequence overcurrent (46): Protects against unbalanced loads and rotor heating.

• Directional power (32): Prevents motoring of the generator and detects reverse power flow.

• Voltage protection: Undervoltage (27), overvoltage (59), and residual overvoltage (59N).

• Frequency protection: Under/overfrequency (81U/O) and rate of change of frequency (81R).

• Thermal overload: For stator and transformer windings, based on measured current and thermal modeling.

All protection stages are independently configurable with definite time or inverse time characteristics (IEC, IEEE, or user-defined curves).

Control and Automation

The terminal includes a powerful programmable logic controller (PLC) functionality that enables users to create customized interlocking, sequencing, and automation schemes. It supports synchronism check (25) and auto-synchronizing for generator connection to the grid, with adjustable phase angle, voltage, and slip limits. The device can control circuit breakers, disconnectors, and tap changers directly via its binary outputs. The integrated disturbance recorder captures up to 120 seconds of fault data with high sampling rates (typically 32 samples/cycle) for detailed post-fault analysis. Measured values (I, U, P, Q, f, cosφ) are displayed locally on the graphical LCD and transmitted via communication links.

Communication and Integration

The REM543CG214AAA A supports multiple communication protocols for seamless integration into substation automation systems. Standard rear communication ports provide options for IEC 61850 (including GOOSE messaging), IEC 60870-5-103, Modbus RTU, and DNP3.0. Redundant Ethernet options are available for high availability in critical applications. Time synchronization via IRIG-B or SNTP ensures accurate event time-stamping. The front panel includes an HMI with keypad and LCD for local operation and configuration, and the device can also be accessed remotely via the protocol gateway. The REM543 is fully compatible with ABB's MicroSCADA and Network Manager systems, as well as third-party SCADA platforms.

Technical Specifications

• Measuring inputs: 4 current inputs (1/5 A) and 4 voltage inputs (100-230 V AC).

• Binary I/O: Up to 24 binary inputs and 16 output relays, depending on configuration.

• Power supply: 80-265 V DC or 100-240 V AC, with wide-range tolerance.

• Case: 6U high, 19" rack or flush mount, IP54 front protection.

• Operating temperature: -10°C to +55°C (extended range available).

• Self-supervision: Continuous hardware and software monitoring with watchdog output.

• Compliance: IEC 60255, IEEE C37.90, and relevant EMC standards.

Typical Applications

The REM543CG214AAA A is widely used in utility power stations, industrial co-generation plants, and renewable energy installations (hydro, wind, solar thermal). It is particularly suited for protecting medium to large generator-transformer blocks where a high degree of reliability and communication integration is required. Its modular design allows it to adapt to various generator types (steam, gas, hydro) and transformer configurations (two-winding, three-winding). The device also finds application in industrial plants with on-site generation, such as paper mills, chemical plants, and steel mills.

With its robust design, comprehensive protection algorithms, and advanced communication capabilities, the ABB REM543CG214AAA A machine terminal ensures reliable operation of critical generation assets, reduces downtime, and simplifies asset management through integration with modern substation automation systems.