ABB DSQC 655 Capacitor Unit 3HAC025562-001 for IRC5 Controllers

IRC5 Capacitor Unit — Technical Overview

This capacitor unit is the energy buffer on the DC link of an ABB IRC5 controller. It is a passive power component: it carries no firmware and holds no configuration, so it is replaced as a physical part rather than a programmed module. ABB lists it as a spare part for the IRC5 M2004 controller module, the IRC5C Compact controller and the IRB 14000 collaborative robot controller.

Specifications

Industrial Applications

• IRC5 Single controller cabinets — standard single-cabinet IRC5 installations across the IRB robot range.
• IRC5C Compact controller cabinets — the compact controller used where cell floor space is limited.
• IRB 14000 (YuMi) controllers — ABB lists this unit under its collaborative robot category.
• High-duty, high-dynamics cells — pick and place, machine tending, palletising and handling cells where axes accelerate and decelerate continuously and the DC link sees constant regenerative peaks.
• Maintenance stock for ageing IRC5 installations — held as a wear-item spare on lines that have been running for many years.

Design Purpose

The unit does three jobs on the DC link. When several axes accelerate at once it delivers current so the bus does not sag. When those axes decelerate it absorbs the regenerated energy so the bus does not climb into an overvoltage trip. In between, it filters ripple so the servo current loops work against a clean, stable bus. In practical terms it protects the power semiconductors in the drive units from the voltage excursions that a multi-axis robot produces on every cycle.

It is also a deliberate wear item. Electrolytic capacitors lose capacitance and gain internal resistance as they age, and heat accelerates that process. A unit that has drifted far enough will still measure "present" but will no longer hold the bus during peaks, which is why bus-related faults on an older controller often lead back here rather than to the drive module.

Common Failure Modes

Symptoms that typically point to an aged or failed capacitor unit:

• DC bus overvoltage or undervoltage faults that keep returning — the classic sign of a bus that no longer has enough buffering. Check the capacitor before replacing a drive module.
• Faults that appear only at peak load — the robot runs fine at low speed or light payload but trips when several axes accelerate together.
• Visible bulging or venting of the capacitor cans, or electrolyte residue and corrosion around the terminals and busbar.
• Localised heat, discolouration or a sharp smell near the unit after a production shift.
• Gradually degrading motion quality — following-error or positioning complaints that worsen over months, caused by a bus that is no longer clean.
• Age-related drift with no visible damage — capacity falls and internal resistance rises long before anything looks wrong, so a controller that has run for many years is a candidate on age alone.

Why Choose Us

• Genuine ABB part, supplied against part number 3HAC025562-001.
• Part number and revision verified against your controller type before dispatch, so you receive the unit that actually matches your cabinet.
• New original or used original available — the condition is confirmed with you before you order.
• Photos and label details of the actual unit provided on request, not stock imagery.
• Support with part-number identification, including the distinction between this unit and the 3HAC026585-001 ultracapacitor kit that also carries the DSQC 655 name.
• Packed for export with the terminals and busbar protected in transit; ships worldwide from Shanghai.
• PayPal, T/T bank transfer and Alibaba Trade Assurance accepted.

Related Products

• 3HAC026585-001 — DSQC 655 Ultracapacitor unit kit. Note this is a different part number: ABB describes it as a kit containing the DSQC 655, an adapter plate and screws (0.626 kg). Order on the full part number, not on "DSQC 655" alone.
• 3HAC029818-001 — DSQC 663 Main Drive Unit, the main drive in the same IRC5 M2004 controller module.
• 3HAC030923-001 — DSQC 664 Additional Drive Unit (ADU HV), used when the cell needs axes beyond the robot's own six.
• 3HAC025338-006 — Main Servo Drive Unit DSQC 617 for IRC5 cabinets.
• 3HAC028357-001 — DSQC 679 FlexPendant teach pendant for IRC5.