ABB 3BHE035301R0410 UNS0121 A-Z UNITROL 1000 Excitation Controller AVR Board

Product Description

The 3BHE035301R0410 (UNS0121 A-Z) is the core digital AVR excitation control board for ABB UNITROL 1000 excitation system. It performs generator voltage regulation, excitation current closed-loop control, reactive power regulation and system protection logic. It samples generator voltage and current signals, outputs firing commands to the power bridge, stabilizes generator terminal voltage under grid and load fluctuation, widely used in synchronous generator excitation cabinets for power plants.

Features

• Part No: 3BHE035301R0410, Type: UNS0121 A-Z, Brand: ABB
• Belongs to UNITROL 1000 series digital automatic voltage regulator (AVR)
• High precision voltage regulation, typical regulation accuracy ±0.5%
• Integrated excitation limit, overexcitation, underexcitation, loss-of-field protection functions
• Supports redundant hot standby configuration for critical generator sets
• Analog sampling, pulse firing output, communication interface for parameter monitoring
• Conformal coating, high vibration and EMC performance for power plant environment
• Front LED indicators for run, fault, communication and alarm status
• Operating temperature: -25°C ~ +55°C
• Configured via ABB UNITROL PC engineering software

Applications

• Thermal power plant synchronous generator excitation cabinet
• Hydropower generator, diesel generator set excitation control
• Industrial captive power plant, marine generator voltage regulation system
• Grid-connected generator set reactive power control and stability control
• Legacy UNITROL 1000 system spare replacement, overhaul and retrofit

FAQ

Q: What is the difference between part number 3BHE035301R0410 and UNS0121 A-Z?
A: 3BHE035301R0410 is the ABB material order number; UNS0121 A-Z is the board type designation of the same excitation controller card.

Q: Which system platform does this board match?
A: It is designed exclusively for ABB UNITROL 1000 static excitation system.

Q: Is this module discontinued?
A: UNITROL1000 series is legacy excitation hardware, original production stopped, supplied as surplus, refurbished and tested spare parts only.

Q: Can it work alone without power bridge unit?
A: No, it is the control board only; it must cooperate with the SCR power bridge unit to complete excitation regulation.