Basler BE1-79A Reclosing Relay

The Basler BE1-79A is a solid‑state automatic reclosing relay designed for overhead distribution lines and transmission systems. It provides sequenced reclosing after a fault trip to restore power automatically, improving service continuity and reducing outage duration. The relay offers independent timing for multiple reclosing attempts and reset intervals.

Reclosing Principle

After a protective relay trips a circuit breaker, the BE1-79A initiates a programmed reclose sequence. It typically provides up to four reclosing shots (reclose attempts) with adjustable time delays between attempts. If the fault is transient, the reclose succeeds and the system returns to normal. If the fault is permanent, the relay locks out after the final unsuccessful attempt, requiring manual reset.

Key Features

• Up to four independent reclosing cycles with adjustable delays.

• Adjustable reset timer to restore initial state after successful reclose.

• Manual lockout reset function.

• Independent timing for each shot: 0.1–300 seconds.

• Wide auxiliary supply: 24–250 VDC or 120/240 VAC.

• LED indication for cycle count and lockout.

• Drawout case for easy installation.

Technical Specifications

The relay operates from a DC or AC auxiliary supply as specified. The timing accuracy is ±2 % or ±50 ms. The relay provides two output contacts: one for the reclose command and one for lockout indication. The contact ratings are 5 A at 250 VAC. The operating temperature range is -20 °C to +60 °C. The relay also includes a test button to simulate a reclose event.

Setting the Reclose Sequence

Each reclose attempt has its own delay setting, typically with decreasing times (e.g., first reclose after 15 seconds, second after 30 seconds, etc.). The reset timer defines the time after a successful reclose before the relay resets to its initial state. The number of reclose attempts is configurable via DIP switches.

Installation and Wiring

Mount the relay in a standard panel. Connect the auxiliary supply to the designated terminals. The reclose output contacts are wired to the circuit breaker’s close coil. The lockout contact can be used for alarm or to prevent further reclosing. The relay also has inputs for external blocking signals (e.g., from a reclosing inhibit relay).

Applications

Primarily used in distribution networks, substations, and industrial plants with overhead lines where transient faults (e.g., lightning strikes) are common. The BE1-79A helps maintain supply continuity for critical loads.

Testing and Commissioning

Simulate a trip signal and observe the reclose sequence. Verify the timing of each shot and the reset function. Ensure lockout occurs after the programmed number of attempts.

Maintenance

Regular inspection of connections and timing verification is recommended. The relay has a long life with minimal maintenance.

Advantages

Compared to electromechanical reclosers, the BE1-79A offers precise timing, flexible programming, and easy integration with modern protection systems.

Compliance

Meets IEEE C37.90 and IEC 60255 standards.

Conclusion

The Basler BE1-79A Reclosing Relay is a reliable solution for automated power restoration, enhancing system reliability and reducing outage times.