Basler Electric BE1‑700V – Digital Multifunction Protective Relay

The Basler Electric BE1‑700V (configuration N3N2X1N) is a versatile digital protective relay designed for comprehensive protection of generators, motors, transformers, and feeders in industrial and utility power systems. This multifunction relay combines protection, metering, and communication in a single compact unit, reducing panel space and simplifying system design.

Protection Elements and Functions

The BE1‑700V incorporates a wide range of protection functions, including:

• Overcurrent protection (50/51) – three‑phase instantaneous and time‑overcurrent with selectable curves.

• Ground fault protection (50N/51N) – residual and zero‑sequence sensing.

• Voltage protection (27/59) – undervoltage and overvoltage with time delay.

• Frequency protection (81O/U) – overfrequency and underfrequency.

• Directional overcurrent (67) – for radial and looped networks.

• Loss‑of‑field (40) – impedance‑based detection for generator protection.

• Negative sequence protection (46) – for unbalanced load and phase loss.

• Thermal overload (49) – for motor and transformer protection.

All elements are independently configurable and can be enabled or disabled as required.

Measurement and Metering

The relay provides high‑accuracy measurement of three‑phase voltage, current, power (kW, kVAR, kVA), power factor, frequency, and energy. All values are displayed on the front‑panel LCD and can be accessed via communication. The unit includes a built‑in oscillography feature that captures up to 64 cycles of waveform data for fault analysis.

Setting and Configuration

Settings are entered via a front‑panel keypad and backlit LCD, or through the BESTCOMS software. Up to six setting groups are available, allowing the relay to adapt to different operating conditions. The unit includes a password‑protected lock to prevent unauthorized changes. A built‑in test mode verifies protection elements without tripping the connected equipment.

Outputs and Indications

The BE1‑700V provides up to six output contacts (form‑C) for trip, alarm, and auxiliary functions. LED indicators show power, pickup, trip, and communication status. A large graphical LCD displays real‑time phasors, trending, and event logs. Target LEDs indicate which protection element operated for the last event.

Communication and Integration

Standard RS‑485 port with Modbus RTU and DNP3 protocols is provided. Optional Ethernet supports Modbus TCP and IEC 61850 for advanced substation integration. The relay includes IRIG‑B input for time synchronization, enabling precise event correlation.

Environmental and Mechanical

Housed in a rugged metal case for panel or 19‑inch rack mounting, the BE1‑700V operates from -40 °C to +85 °C and is rated IP40. The relay meets IEC 60255, IEEE C37.2, and ANSI C37.90 standards, and carries CE and UL certifications.

Typical Applications

This relay is used for protection of medium‑voltage motors, distribution transformers, generator units (up to 50 MW), and industrial feeders. Its multifunction capability makes it suitable for both primary and backup protection schemes.

Maintenance and Diagnostics

Continuous self‑diagnostics monitor hardware and software integrity. The relay logs events and provides diagnostic codes for troubleshooting. Periodic functional testing of protection elements is recommended, with test procedures documented in the user manual.

In summary, the Basler Electric BE1‑700V offers a comprehensive, flexible, and reliable protection solution for a wide range of power system assets.