DSQC 668 (3HAC029157-001) is the axis computer board within the ABB IRC5 robot controller — the dedicated motion control processor responsible for calculating joint trajectories, processing servo control commands, and generating output signals to drive the motor modules for each controlled axis. Designated DSQC 668 and ordered under part number 3HAC029157-001, this printed circuit board is housed in a robust aluminium alloy enclosure measuring 269 × 147 × 27 mm and weighing 0.58 kg, operating on a 24V DC supply from the IRC5 power distribution system. It functions as the intelligent core of the IRC5 axis control architecture, interfacing directly with the drive units and the IRC5 main computer to execute real-time position and velocity control loops. The DSQC 668 is available through Atlantech Drives — typical delivery 1–2 weeks, worldwide express shipping, 12-month warranty.
What Is the DSQC 668 (3HAC029157-001)?
The DSQC 668 is a programmable axis computer within the IRC5 controller family, operating as the motion intelligence layer between the IRC5 main computer and the drive power electronics. While the main computer (DSQC 679 or DSQC 1000) handles program execution, path planning at the task level, and HMI communication, the DSQC 668 executes the real-time servo loops — typically running at update rates well above 1 kHz — that translate path data into precise motor torque commands for each robot axis. A failed or degraded DSQC 668 manifests as axis-specific errors rather than system-wide failures: the IRC5 will report joint position errors, servo faults on specific axes, or motor commutation failures for the axes managed by the affected board, while axes managed by a functioning DSQC 668 continue to operate normally. This axis-specific fault signature is the primary diagnostic indicator that distinguishes DSQC 668 failure from main computer or power supply faults.
Key Technical Specifications
- Part Number: 3HAC029157-001
- Secondary Reference: DSQC 668
- Function: Axis Computer — motion control processor for IRC5 robot axes
- Supply Voltage: 24V DC
- Housing Material: Aluminium alloy
- Net Weight: 0.58 kg
- Dimensions (D × W × H): 269 × 147 × 27 mm
- Compatible System: ABB IRC5 robot controller (all variants)
- Country of Origin: China (CN)
- Customs Tariff Number: 84714100
- Product Category: Printed Circuit Board — IRC5 Spare Parts
- Minimum Order Quantity: 1 unit
Architecture & Design Overview
The DSQC 668 operates within the IRC5 control architecture as part of the axis control layer, which sits between the main computer and the drive power electronics. The IRC5 controller uses a distributed processing architecture: the main computer handles task-level program execution and path planning, while the DSQC 668 executes the inner servo control loops that manage actual motor position, velocity, and current in real time. Communication between the main computer and the DSQC 668 occurs over the IRC5 internal control bus, using a deterministic protocol that guarantees the servo update cycle timing required for coordinated multi-axis motion. The aluminium alloy housing provides both mechanical rigidity and thermal dissipation — the DSQC 668 generates heat during continuous high-speed motion and relies on the IRC5 cabinet’s forced-air cooling system to maintain operating temperature within specification. In IRC5 MultiMove configurations, where multiple robot manipulators share a single controller, the axis computer architecture scales by adding additional DSQC 668 boards — each managing a defined subset of axes across the combined manipulator group.
DSQC 668 as a Replacement for Earlier IRC5 Axis Computer Revisions — Compatibility Notes
The DSQC 668 (3HAC029157-001) represents the current standard axis computer revision for the IRC5 platform. Earlier IRC5 installations may contain earlier hardware revisions of the axis computer board under different sub-designations within the DSQC 668 family. When replacing an earlier revision with a 3HAC029157-001, engineers should verify the RobotWare version compatibility using the ABB Service Information System before procurement — ABB publishes minimum RobotWare revision requirements for each hardware change level of the DSQC 668. In most IRC5 installations running RobotWare 5.10 or later, the 3HAC029157-001 is a direct drop-in replacement requiring no additional configuration after installation. The IRC5 main computer automatically detects the axis computer on the internal bus during startup and loads the appropriate firmware. If the IRC5 generates an «Axis Computer Communication Error» after installing a replacement DSQC 668, this indicates either a bus connection issue (recheck the board connector seating) or a RobotWare version that requires an update before recognising the new hardware revision. Compatibility with non-standard IRC5 configurations including MultiMove and paint variants should be confirmed with ABB technical support before replacement.
Maintenance Recommendations
The DSQC 668 has no field-serviceable components and no user-adjustable parameters — maintenance consists of environmental monitoring and visual inspection rather than periodic calibration. Inspect the board connector pins annually in high-vibration environments: the 269 mm depth of the board creates leverage that can stress the connector interface during sustained vibration, causing intermittent contact faults that manifest as transient axis errors. These are frequently misdiagnosed as motor or drive failures before the board connector is identified as the root cause. Ensure the IRC5 cabinet door seals are intact and the air filter is replaced on schedule — the DSQC 668 is not rated for particulate contamination, and dust accumulation on the board surface reduces thermal dissipation efficiency, shortening the component service life. When removing the DSQC 668 for inspection or replacement, use an ESD wrist strap — the board contains static-sensitive components. Store removed boards in antistatic packaging; exposure to electrostatic discharge during handling is the most common cause of latent failures in replacement boards that present no visible damage.
Frequently Asked Questions
Q: How do I confirm the DSQC 668 (3HAC029157-001) is the failed component rather than the drive module or motor?
A: DSQC 668 failure is characterised by axis-specific faults — errors that affect only the axes managed by that board, while other axes continue to function normally. Drive module or motor failures typically produce different error codes related to current feedback or motor temperature. If the IRC5 reports axis computer communication errors specifically, and swapping the motor and drive with known-good units does not resolve the fault, the DSQC 668 is the likely cause. Confirm by checking the IRC5 event log for DSQC 668 bus communication errors.
Q: Can the DSQC 668 be replaced without recalibrating the robot axes?
A: Yes. The DSQC 668 is a motion control processor — it does not store axis calibration data. Robot calibration is stored in the IRC5 main computer and the resolver/encoder absolute position system of the manipulator. Replacing the DSQC 668 does not affect calibration data, and no recalibration procedure is required after installation. However, the IRC5 system must be restarted after replacement to initialise the new board on the internal bus.
Q: Is there a visible way to confirm the DSQC 668 has failed before ordering a replacement?
A: Check the LED indicators on the DSQC 668 board face with the IRC5 cabinet open and powered on. A healthy board shows steady green status LEDs; absent or red LEDs indicate a board fault. Additionally, the ABB FlexPendant event log will show DSQC 668-specific error codes if the board is failing to communicate on the internal bus. Visual inspection for burnt components, bulging capacitors, or corrosion on the connector pins can identify physical damage, though many electronic failures produce no visible symptoms.
Do you need more references from this brand? Explore our full catalog of ABB here: https://atlantechdrives.com/manufacturers/abb/
