Technical Specifications

Main Features and Advantages

The ABB DSQC661​ (3HAC026253-001) earns its place as the default I/O power supply in the IRC5 ecosystem not through headline-grabbing specs, but through a set of quietly critical design decisions that directly reduce unplanned downtime in live production cells.

Fanless convection cooling.​ Unlike drive-unit supplies that rely on forced-air fans—mechanical components with a finite lifespan that accumulate dust and eventually seize—the 3HAC026253-001​ uses passive convection cooling. This eliminates the most common wear-item in cabinet power electronics, reduces audible noise on the shop floor, and prevents fan-failure cascades where a stalled fan takes the supply offline and triggers a robot fault. In high-dust environments such as welding or machining cells, removing the fan also removes the vacuum effect that otherwise pulls conductive particulates into the PCB.

Wide-input tolerance for volatile mains.​ The ABB DSQC661​ accepts 180–290 V AC on its primary, meaning it comfortably rides through minor sags and swells on the facility side without dropping the 24 V DC output. Paired with the upstream IRC5 transformer (which offers selectable taps at 200 V / 380 V / 400 V / 480 V depending on regional mains), the unit forms a two-stage buffer: the transformer takes the worst of the line volatility, and the 3HAC026253-001​ refines the remaining ripple into clean DC for sensitive I/O logic.

Integrated protection suite.​ Overvoltage, overload, and short-circuit protection are hardware-level, self-recovering where appropriate, and reported back to the controller via the IRC5 backplane. This means a downstream I/O board short doesn’t silently damage the supply—it trips, protects itself, and logs the event so maintenance can pinpoint the offending module rather than chasing ghost faults.

EMI filtering and logic-domain tuning.​ Because the ABB DSQC661​ feeds the I/O and main-computer rails rather than motor drives, its output filtering is tuned for low-noise logic rather than high-current pulse tolerance. This matters: digital inputs from encoders, safety light curtains, and fieldbus adapters are far more sensitive to DC-rail ripple than motor drive stages, and the 3HAC026253-001​ is specifically voiced for that domain.

Drop-in replacement for DSQC 627.​ Early IRC5 M2000 cabinets used the DSQC 627 as the I/O supply; as those cabinets age, the 3HAC026253-001​ provides a verified successor with higher efficiency and modern protection, allowing retrofit without rewiring the 24 V distribution loom.

Application Field

The ABB DSQC661​ (3HAC026253-001) lives inside ABB control cabinets across virtually every sector where ABB robotics are deployed. Its primary mission is delivering a stable 24 V DC logic rail to every I/O module, fieldbus adapter, and safety circuit in the cabinet, which makes it foundational to any process that cannot tolerate an unplanned robot reboot.

In automotive body-in-white and powertrain lines, the ABB DSQC661​ powers the I/O backplane for IRB 6600 and IRB 7600 spot-welding cells where duty cycles run 24/7 and a single controller reboot triggered by a sagging 24 V rail can scrap an entire carrier of parts. Here the fanless design is especially valued—weld-cell particulate would normally clog a forced-air supply fan within months, but the 3HAC026253-001​ runs convection-cooled with no intake path for spatter dust.

In electronics and consumer-goods assembly, Compact cabinets with IRB 1600 or IRB 2600 manipulators use the ​ to feed high-density DSQC 652 digital I/O boards and DSQC 651 analog I/O boards that manage feeder arrays, vision triggers, and conveyor interlocks. The wide-input range matters in global EMS (electronics manufacturing services) facilities where the same cell design gets deployed across plants in Europe (230 V), North America (208/240 V), and Asia (200–220 V) without respecifying the power supply.

In metal fabrication and machining cells where IRB 4600 and IRB 6700 handle material removal, the 3HAC026253-001​ sits alongside DSQC 662 (drive supply) in Dual Cabinet configurations: the 662 feeds the axis drives, while the ​ owns the I/O and safety domain. This separation of concerns is deliberate—mixing logic and drive currents on a single supply is a known failure mode when axis regen events inject noise onto the DC rail.

For system integrators upgrading legacy M2000 cabinets, swapping a failing DSQC 627 for a 3HAC026253-001​ is a common modernization step that brings CE/UL-grade protection and 90 % efficiency to older cells without a full controller replacement—extending the economic life of the robot by another 5–8 years.