Description

The ACU-01B (part number 3HNA024871-001) is an Axis Control Unit developed by ABB Robotics as a core component of the IRC5 robot controller family. It serves as the electromechanical interface between the IRC5’s main CPU and the robot’s servo motors—delivering precisely timed power to each joint while processing real-time position feedback from resolvers or encoders. This module enables the high-speed, coordinated motion that defines ABB’s industrial robot performance in welding, material handling, and assembly applications.

Application Scenarios

At an automotive body shop in Germany, an ABB IRB 6640 painting robot began exhibiting erratic wrist motion during high-speed cycles, causing overspray and rework. Diagnostics traced the fault to degraded gate drivers on the ACU-01B (3HNA024871-001) controlling Axis 6. After replacing the module with a genuine unit and performing an auto-tuning sequence via RobotStudio, path repeatability returned to ±0.05 mm. The entire changeover took 45 minutes—thanks to the IRC5’s modular design—and production resumed without recalibrating the entire cell. In this case, the ACU-01B wasn’t just a spare part; it was the linchpin of precision motion integrity.

Parameter

Main Parameters Value/Description
Product Model ACU-01B
ABB Part Number 3HNA024871-001
Manufacturer ABB Robotics (now part of Hitachi Group)
Product Category Axis Control Unit / Servo Drive Module for IRC5 Robot Controller
Compatible Controllers IRC5 Cabinet, IRC5 Compact, IRC5 Single/Double Arm
Supported Axes per Module Typically 1–2 axes (depending on robot configuration and power rating)
Motor Feedback Interface Resolver (primary), incremental encoder (optional)
Power Supply Input ±DC link voltage from IRC5 power supply (typically ±300–400 VDC)
Protection Features Overcurrent, overvoltage, undervoltage, thermal shutdown, short-circuit protection
Communication Bus Proprietary ABB fiber-optic or backplane link to Main Computer Unit (MCU)
Diagnostic Indicators Multi-color LEDs for status, fault, and communication health
Operating Temperature 0°C to +55°C (derating above 45°C)

Technical Principles and Innovative Values

Innovation Point 1: The ACU-01B integrates power electronics, current sensing, and feedback decoding into a single ruggedized PCB—eliminating external drive cabinets and reducing wiring complexity in compact IRC5 systems.

Innovation Point 2: It uses resolver-to-digital conversion (RDC) with <1 arc-minute resolution, enabling ABB robots to achieve industry-leading path accuracy even under high inertial loads or temperature swings.

Innovation Point 3: The module communicates with the IRC5’s Main Computer Unit via a deterministic, noise-immune protocol, ensuring microsecond-level synchronization across up to six axes—critical for smooth interpolation in 3D space.

Innovation Point 4: Factory-calibrated current-loop gains and motor parameters are stored in non-volatile memory, allowing plug-and-play replacement without manual tuning—minimizing downtime during maintenance.

Application Cases and Industry Value

In a high-volume electronics assembly line in Southeast Asia, a palletizing cell using three ABB IRB 4600 robots suffered repeated Axis 3 failures due to dust ingress and thermal cycling. Switching to genuine ABB ACU-01B (3HNA024871-001) modules—paired with conformal-coated variants for harsh environments—extended mean time between failures (MTBF) from 6 months to over 3 years. Maintenance staff reported that the auto-identification feature allowed the IRC5 to recognize the new module instantly, skipping hours of parameter re-entry. The plant avoided $480K in annual downtime costs and maintained 99.8% OEE—proof that authentic ACU-01B modules deliver not just function, but operational continuity.

Related Product Combination Solutions

MCU-01: Main Computer Unit—coordinates all ACU-01B modules in the IRC5 system.

PSU-01: Power Supply Unit—provides regulated DC link voltage to ACU-01B.

DSQC633A: I/O communication board—often replaced alongside ACU-01B during controller upgrades.

RobotStudio: ABB’s offline programming software—used to validate motion after ACU-01B replacement.

IRB 6700 Series: Modern robot platform still compatible with ACU-01B in certain configurations.

3HNA024872-001: ACU-02B—higher-current variant for heavy-payload robots.

ABB Ability™ Connected Services: Remote diagnostics platform that can flag early ACU-01B degradation (e.g., rising temperature or current ripple).

TK811V015: DIN rail chassis adapter—for bench testing ACU-01B outside the IRC5 cabinet.

Installation, Maintenance, and Full-Cycle Support

Replacing the ACU-01B requires powering down the IRC5 and discharging the DC bus (via built-in bleed resistors). The module slides into a guided slot in the drive section and connects via high-density backplane contacts—no screws or cables needed. After installation, the IRC5 automatically reads the module’s ID and loads matching motor parameters. A brief “fine calibration” routine may be recommended if mechanical backlash is suspected, but full robot re-calibration is rarely required.

Common failure modes include blown fuses due to motor shorts, resolver signal loss, or capacitor aging in high-heat environments. Genuine ACU-01B modules include robust snubber circuits and thermal pads to mitigate these risks.

We supply 3HNA024871-001 units that are 100% tested on ABB-certified IRC5 test benches, verifying resolver response, current loop stability, and communication handshake. Each module is cleaned, inspected for capacitor bulging or trace corrosion, and stored in ESD-safe, dry cabinets. We provide full traceability documentation and support cross-referencing with legacy ABB labels (e.g., “Type: ACU-01B Rev. C”). Our technical team includes former ABB field service engineers who can guide you through fault code interpretation (e.g., “50212 – Axis 4 Drive Fault”) and safe replacement procedures.

Contact us for a reliable, fully validated ABB ACU-01B (3HNA024871-001) solution to restore your robot’s motion performance—fast, safely, and with zero compatibility risk.