Basler BE1‑25 Solid State Time Overcurrent Relay

The Basler BE1‑25 is a solid‑state time overcurrent relay designed for protection of distribution feeders, transformers, and motors. This model, with configuration code M1EA6PA5S1F, offers reliable detection of phase and ground faults with adjustable time‑current characteristics. It is part of Basler Electric's BE1 series, known for high accuracy and robust construction in utility and industrial environments.

Key Features

The BE1‑25 features a wide pickup current range, selectable inverse‑time and definite‑time curves, and a high reset ratio. It includes a target indicator for fault identification and test points for calibration. The relay provides both instantaneous and time‑delayed trip outputs. Its solid‑state design ensures long‑term stability and immunity to vibration.

Technical Specifications

CT secondary rating: 5 A or 1 A. Pickup range: 0.5‑20 A (for 5 A CT). Time dial: adjustable from 0 to 10. Time‑current curves: IEC or IEEE inverse, very inverse, extremely inverse, and definite time. Instantaneous element: adjustable from 2‑40 times pickup. Output contact rating: 5 A at 250 VAC. Operating temperature: -20°C to +55°C. Auxiliary supply: 120/240 VAC or 48/125 VDC.

Operating Principles

The relay continuously monitors the current from CTs. When the current exceeds the pickup setting, the timing circuit initiates. The time delay is determined by the selected curve and time dial setting. If the fault persists, the output relay trips the breaker. The instantaneous element operates without intentional delay for high‑current faults, providing fast protection.

Applications

This relay is used in utility substations, industrial power systems, and commercial buildings for feeder and motor protection. It is also suitable for transformer backup protection and as a main overcurrent relay in distribution panels.

Installation and Configuration

Mount the relay in a standard panel cutout. Connect the CT leads, auxiliary power, and trip circuits. Set the pickup, time dial, and instantaneous pickup using the front‑panel knobs. A secondary injection test is recommended to verify the time‑current characteristic.

Maintenance and Reliability

Routine maintenance includes visual inspection and periodic calibration checks. The solid‑state design provides high reliability with no moving parts. The relay is protected against transients and surges for long service life.

Conclusion

The Basler BE1‑25 solid state time overcurrent relay offers dependable overcurrent protection with flexible settings, making it a versatile choice for modern power distribution systems.