Basler BE1-51A Overcurrent Relay

The Basler BE1-51A (model K1E-W6M-B1N1F, also referenced as BE151AK1EW6MB1N1F) is a high-performance digital overcurrent relay designed for generator, transformer, and feeder protection. This relay provides phase overcurrent (51) and ground overcurrent (51N) protection with programmable time-current curves, offering excellent coordination flexibility. The BE1-51A is ideal for demanding utility and industrial applications where precise protection and reliability are critical.

The relay features advanced measurement and control capabilities, including directional overcurrent elements (optional), event recording, and comprehensive diagnostics. It includes a user-friendly interface with a high-resolution display and keypad, and supports Modbus RTU or DNP3 communication for seamless integration with SCADA systems. The BE1-51A is built with rugged hardware for reliable operation in harsh environments.

Technical Specifications

• Model: BE1-51A (K1E-W6M-B1N1F)

• Protection functions: Phase overcurrent (51), ground overcurrent (51N), directional overcurrent (67) – optional

• Current sensing: 1/5 A CT inputs

• Time-current curves: Definite time, IEC, IEEE, and user-definable curves

• Pickup range: 0.05-20.00 A (adjustable)

• Time dial: 0.05-15.00 (adjustable)

• Accuracy: ±1% of pickup

• Output contacts: 4 form C (trip, alarm, etc.)

• Communication: Modbus RTU (RS-485) or DNP3 (optional)

• Power supply: 24-240 V AC/DC (universal)

• Display: 4-line alphanumeric LCD with keypad

• Event recording: 64 events, 20 fault records

• Operating temperature: -40°C to +70°C

• Certifications: CE, UL, RoHS

Functional Features

• Overcurrent protection: Phase and ground fault protection with multiple curve options for precise coordination.

• Directional element (optional): Enables directional overcurrent protection for system selectivity.

• Programmable logic: Allows custom logic equations for advanced protection schemes.

• High accuracy: ±1% ensures reliable protection and coordination.

• Event recording: Stores fault data for post-fault analysis and system optimization.

• Communication: Modbus or DNP3 enables remote monitoring and setting changes.

Typical Applications

• Generator protection: Phase and ground fault backup protection.

• Transformer protection: Overcurrent protection for power transformers.

• Feeder protection: Protection of distribution feeders and cables.

• Motor protection: Overcurrent and ground fault protection for large motors.

• Bus protection: Backup overcurrent protection for substation buses.

Installation and Configuration

Mount the BE1-51A on a panel. Connect the CT inputs, power supply, and output contacts. Configure the protection elements, time-current curves, and communication settings using the front-panel keypad or via communication. The relay includes comprehensive test and diagnostic tools for commissioning and maintenance.

Compliance

Complies with IEEE C37.90, IEC 60255, CE and UL approved, RoHS compliant.

Conclusion

The Basler BE1-51A provides advanced, flexible overcurrent protection for generators, transformers, and feeders, offering precision, reliability, and extensive communication capabilities for modern power systems.