ABB UNITROL 1010 3BHE035301R1002 Redundant Excitation Control Module
June 08, 2026

ABB UNITROL 1010 3BHE035301R1002 Redundant Excitation Control Module

The ABB UNITROL 1010 3BHE035301R1002 is a high‑performance, microprocessor‑based redundant digital excitation controller (AVR) belonging to ABB’s UNITROL 1000 series. It is engineered for small‑to‑medium synchronous generators up to 100 MVA and provides 1+1 hot‑standby redundancy with seamless failover for maximum operational reliability. Designed for both brushless and static excitation systems, this module integrates advanced regulation, automatic synchronization, comprehensive protection, and industrial communication into a compact, rugged unit, making it ideal for critical power generation applications where uninterrupted operation is paramount.

Description

ABB UNITROL 1010 3BHE035301R1002 Redundant Excitation Control Module

Product Overview

The ABB UNITROL 1010 3BHE035301R1002 is a high‑performance, microprocessor‑based redundant digital excitation controller (AVR) belonging to ABB’s UNITROL 1000 series. It is engineered for small‑to‑medium synchronous generators up to 100 MVA and provides 1+1 hot‑standby redundancy with seamless failover for maximum operational reliability. Designed for both brushless and static excitation systems, this module integrates advanced regulation, automatic synchronization, comprehensive protection, and industrial communication into a compact, rugged unit, making it ideal for critical power generation applications where uninterrupted operation is paramount.

Key Features

Redundant Hot‑Standby Architecture

This model features a dual‑channel 1+1 hot‑standby configuration with an automatic failover time of less than 5 ms, ensuring no single point of failure and bumpless transfer during channel switching. The redundant design is certified to SIL 2 (IEC 61508) safety integrity level, meeting stringent requirements for critical power plant control systems. A dedicated high‑speed link synchronizes the master and standby channels, enabling identical control parameters and fast, reliable switchover.

Precision Voltage Regulation & Control Modes

Delivers industry‑leading ±0.2% steady‑state voltage regulation accuracy and a dynamic response time of less than 25 ms, compliant with IEEE 421.5 and IEC 61000‑6‑2 standards. It supports four primary control modes with bumpless transfer: automatic voltage regulation (AVR), constant reactive power (VAR), constant power factor (PF), and manual field current control. The integrated automatic synchronization (SYNC) function automates voltage matching, phase alignment, and frequency synchronization for safe, seamless grid connection.

Comprehensive Protection & Monitoring

Built‑in protective functions safeguard the generator and excitation system against over‑excitation, under‑excitation, field overcurrent, loss‑of‑excitation, overvoltage/undervoltage, overtemperature, and short‑circuit faults. Real‑time monitoring includes rotating diode health check for brushless systems, while an integrated event logger records time‑stamped fault data, operational events, and system parameters for predictive maintenance, troubleshooting, and compliance reporting.

Robust Hardware & Environmental Adaptability

The module features a compact, all‑in‑one design with an IP20 protection rating and conformal‑coated PCB to withstand harsh industrial environments, including dust, moisture, and temperature extremes. It operates reliably across a wide temperature range of ‑25°C to +70°C (storage temperature: ‑40°C to +85°C), withstanding 5%–95% non‑condensing humidity and altitudes up to 2000 m. The metal chassis enhances mechanical stability and electromagnetic shielding, while the panel‑mountable form factor minimizes cabinet space requirements.

Versatile I/O & Industrial Communication

Equipped with 4 analog inputs (CT/PT, 0–10 V, 4–20 mA), 2 analog outputs, 8 digital inputs, and 6 digital outputs for seamless integration with generator, grid, and auxiliary systems, plus a 24 V DC/600 mA output for external relays. Communication interfaces include Modbus RTU (RS‑485), Modbus TCP, CANopen, and USB (for configuration via ABB’s CMT 1000 tool), with optional IEC 61850 support for modern grid communication. This enables easy connectivity to PLC, SCADA, DCS (e.g., ABB 800xA), and third‑party systems.

Wide Compatibility & Certifications

Fully compatible with ABB UNITROL 1010 series rectifiers, power supplies, and accessories, as well as standard CT/PT signals and third‑party control equipment. It complies with global standards including CE, UL, RoHS, DNV‑GL, and SIL 2, ensuring suitability for industrial, marine, and power plant applications worldwide.

Technical Specifications

  • Manufacturer: ABB

  • Model: 3BHE035301R1002 (UNITROL 1010 Redundant)

  • Product Type: Redundant Digital Excitation Controller / AVR with Synchronization

  • Applicable Generators: Up to 100 MVA synchronous generators (50/60 Hz)

  • Excitation Compatibility: Brushless and static excitation systems

  • Input Power Supply: 85–264 VAC, 50/60 Hz (110/220 VAC switch‑selectable); dual power input for redundancy

  • Excitation Output: 0–300 V DC, up to 10 A continuous

  • Power Consumption: ≤40 VA

  • Voltage Regulation Accuracy: ±0.2% (steady state); ±0.5% (transient)

  • Dynamic Response Time: <25 ms (95% step response)

  • Control Modes: AVR, Constant VAR, Constant PF, Manual Field Current

  • Analog I/O: 4 AI / 2 AO

  • Digital I/O: 8 DI / 6 DO

  • Communication: Modbus RTU/TCP, RS‑485, CANopen, USB; optional IEC 61850

  • Protection Functions: Over‑excitation, under‑excitation, field overcurrent, loss‑of‑excitation, overvoltage, undervoltage, overtemperature, short‑circuit

  • Redundancy: 1+1 hot‑standby, <5 ms failover, SIL 2 certified

  • Operating Temperature: ‑25°C to +70°C

  • Storage Temperature: ‑40°C to +85°C

  • Humidity: 5%–95% non‑condensing

  • Protection Class: IP20

  • Dimensions (W×H×D): 120 × 260 × 85 mm

  • Weight: Approximately 2.5 kg

  • Certifications: CE, UL, RoHS, DNV‑GL, SIL 2 (IEC 61508)

Core Functions

The UNITROL 1010 3BHE035301R1002 performs closed‑loop excitation control by real‑time sampling of generator voltage, current, and grid parameters. It executes advanced PID control algorithms to adjust thyristor firing angles, stabilizing output voltage and damping low‑frequency oscillations. The integrated SYNC function automates grid connection by matching voltage, frequency, and phase between the generator and grid. The dual‑channel redundancy ensures continuous operation even if one channel fails, with automatic failover preserving control integrity. The module also provides system‑wide health monitoring, fault diagnosis, and protective tripping/de‑excitation commands, with data logging for maintenance compliance and performance analysis.

Typical Applications

  • Critical Power Plants: Small‑to‑medium hydroelectric, thermal, and gas‑fired power plants (5–100 MVA) requiring high reliability and redundancy.

  • Industrial Captive Power: Steel, chemical, petrochemical, and pulp/paper facilities with on‑site generators for critical load support.

  • Marine Power Systems: Ships, offshore platforms, and marine vessels complying with DNV‑GL standards for reliable power generation.

  • Grid‑Connected & Isolated Operation: Generators needing seamless grid synchronization and stable standalone operation.

  • Retrofit Projects: Direct replacement for legacy ABB UNITROL 500/1000 series AVRs, adding modern digital control and redundancy with minimal cabinet modification.


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