Basler Electric BE1‑27 Solid State Protective Relay

The Basler Electric BE1‑27 (model A3E C3J A1N6F) is a solid‑state undervoltage relay designed to protect electrical equipment from damage caused by sustained low voltage conditions. It monitors single‑phase or three‑phase AC voltages and trips when the voltage falls below a preset threshold for a selected time delay. This relay is commonly used in motor protection, generator protection, and automatic transfer schemes to prevent equipment overheating, stalling, or improper operation.

Operating Principle

The relay continuously measures the RMS voltage of the monitored circuit. When the voltage drops below the pickup setting (adjustable from 1 to 300 VAC) for a selected time delay (0.1‑10 seconds), the relay operates its output contacts. A built‑in filter reduces harmonics and transient noise to prevent nuisance tripping. The relay includes a target indicator for trip identification and a reset pushbutton.

Key Features

Front‑panel potentiometers allow adjustment of pickup voltage and time delay. LED indicators show voltage presence and trip status. A test pushbutton enables functional verification. Output contacts: 1 Form C (SPDT) rated 5 A at 250 VAC. The relay is housed in a rugged metal enclosure suitable for panel mounting. It operates from a wide range of DC or AC control voltages.

Technical Specifications

Input voltage: 1‑300 VAC, 50/60 Hz. Pickup accuracy: ±2% of setting. Time delay accuracy: ±3% or 50 ms. Output contacts: 1 SPDT, 5 A at 250 VAC. Power supply: 24‑250 VDC or 120‑240 VAC. Burden:<5 VA. Operating temperature: –20°C to +65°C. Meets ANSI/IEEE C37.90 surge withstand.

Applications

The BE1‑27 is used on motor control centers, generator voltage regulators, and automatic transfer switches. It provides protection against brownouts, load shedding, and loss of source. It can be coordinated with overvoltage relays to provide complete voltage protection.

Installation and Commissioning

Mount the relay in a standard panel cutout. Connect voltage sensing leads and control power. Commissioning involves setting the pickup and time delay values, then testing with a variable AC source to verify trip accuracy. The relay includes a built‑in test jack for signal injection.

Reliability and Quality

Basler Electric’s BE1‑27 is built with solid‑state technology and conformal coating for environmental resilience. It is factory calibrated and requires minimal maintenance. The relay has a long service life and proven performance in critical applications.

Conclusion

The Basler Electric BE1‑27 solid‑state undervoltage relay (A3E C3J A1N6F) is a precise, reliable, and easy‑to‑use protection device for undervoltage conditions. Its adjustable settings and robust construction make it an essential component in any power system protection scheme.