ABB 3BHE030579R0003 UNITROL 1020 Automatic Voltage Regulator Product Description

The ABB 3BHE030579R0003, also known as UNITROL 1020 (UNS0119A‑Z V1), is a high‑precision digital automatic voltage regulator (AVR) engineered by ABB for excitation control of synchronous generators. It delivers precise voltage regulation and system stability for power generation and industrial applications, built on decades of ABB power electronics and control expertise.

Designed for synchronous generators in static excitation systems, the unit achieves a typical voltage regulation accuracy of ±0.5% (0.2% at 25°C) and a fast response time of <20 ms for three‑phase measurements, effectively suppressing voltage fluctuations and ensuring stable grid integration. It supports a wide DC power supply range of 12.5 VDC to 48 VDC and handles a maximum continuous excitation current of 40 A, suitable for both small‑to‑medium generators and large‑scale power plant units.

The regulator features comprehensive protection functions including over‑excitation, under‑excitation, over‑voltage, under‑voltage, over‑current, and loss‑of‑excitation protection, safeguarding the generator and excitation system from electrical faults. It integrates four digital inputs, two digital outputs, and one ±10 VDC analog input for flexible signal interfacing with field sensors, switches, and control devices.

For communication, the 3BHE030579R0003 is equipped with Modbus RTU (RS‑485), USB, and optional Ethernet interfaces, enabling seamless data exchange with PLCs, SCADA systems, and remote monitoring platforms. Configuration, parameter tuning, and diagnostics can be performed via ABB’s CMT1000 software, supporting real‑time measurement, setpoint adjustment, and PID optimization.

Built for harsh industrial environments, the unit has a rugged metal enclosure with IP20 protection, conformal coated PCB, and a wide operating temperature range of -25°C to +70°C (extended -40°C to +70°C available). It weighs approximately 3.8 kg with dimensions 250 × 150 × 140 mm, supporting both panel and standard cabinet mounting.

Certified to CE, UL, and RoHS standards, the ABB 3BHE030579R0003 UNITROL 1020 AVR meets global safety and quality requirements. It is widely applied in thermal power plants, hydroelectric stations, marine electrical propulsion, traction locomotives, and wind power systems, ensuring reliable voltage control and enhancing the efficiency and lifespan of synchronous generators.