DSQC 653 (3HAC025918-001) is the Digital I/O module with relay outputs for the ABB IRC5 robot controller — an 8-input, 8-output DeviceNet distributed I/O device where the outputs are relay contacts rather than the solid-state transistor outputs found in the DSQC 652 (3HAC025917-001).
Ordered under part number 3HAC025918-001 and designated DSQC 653 (option 718-2), this module operates at 24V DC on the IRC5 DeviceNet master bus. The relay output architecture makes it the correct choice for applications requiring galvanic isolation between the robot controller and the controlled device, or for switching loads that exceed the current capacity of solid-state transistor outputs.
Atlantech Drives supplies the DSQC 653 with an estimated lead time of 1–2 weeks. Request your quote for worldwide shipping and 12-month warranty.
What Is the DSQC 653 (3HAC025918-001)?
The DSQC 653 is the relay output variant of the ABB IRC5 digital I/O module family. While the DSQC 652 uses solid-state transistor outputs (24V DC switching), the DSQC 653 uses electromechanical relay contacts — providing complete galvanic isolation between the control circuit (the IRC5) and the load circuit (the controlled device).
This isolation is critical in applications where the controlled load operates at a different voltage from the IRC5 control system — for example, switching a 230V AC solenoid valve or a 48V DC motor contactor coil directly from the robot I/O. The relay contacts switch the load circuit independently of the IRC5’s 24V DC logic supply, without requiring additional external isolation relays.
Like all IRC5 DeviceNet I/O modules, the DSQC 653 requires explicit configuration in RobotStudio after installation — node address assignment via DIP switches and signal definition in the system parameters before the I/O channels are accessible to RAPID programs.
Key Technical Specifications
- Part Number: 3HAC025918-001
- Secondary Reference: DSQC 653
- ABB Designation: Digital I/O with relay outputs — IRC5 option 718-2
- Function: Digital I/O module with relay contact outputs for IRC5
- Communication: DeviceNet (distributed I/O device)
- Operating Voltage: 24V DC (control circuit)
- Digital Inputs: 8 channels
- Digital Outputs: 8 channels — relay contacts (galvanically isolated)
- Output Type: Electromechanical relay — not solid-state
- Compatible System: ABB IRC5 M2004 — all variants
- Minimum Order Quantity: 1 unit
DSQC 653 vs. Related ABB IRC5 DeviceNet I/O Modules — Series Comparison
| Model | Part Number | Digital Inputs | Digital Outputs | Output Type | Galvanic Isolation |
|---|---|---|---|---|---|
| DSQC 651 | 3HAC025784-001 | 8 | 8 | Solid-state + 2 AO | Optical (digital) |
| DSQC 652 | 3HAC025917-001 | 16 | 16 | Solid-state transistor | Optical |
| DSQC 653 | 3HAC025918-001 | 8 | 8 | Relay contacts | Full galvanic |
| DSQC 355A | — | 0 | 0 | Analog ±10V | — |
Data sourced from official ABB manufacturer documentation. Contact Atlantech Drives to verify current availability of specific models.
Typical Industrial Applications
The DSQC 653 is the preferred choice when the robot cell includes loads that cannot be switched by 24V DC solid-state outputs. Common applications include switching 230V AC solenoid valves, 110V AC signal lamps or alarm devices, motor starter coils operating at different voltages, and any load where electrical noise immunity requires complete galvanic separation from the IRC5 control circuit.
In welding robot cells, the DSQC 653 is frequently used to interface the IRC5 with welding equipment that uses different supply voltages for its control inputs. The relay contacts prevent welding current transients from coupling back into the IRC5 through the I/O lines — a failure mode that damages solid-state outputs in high-noise environments.
Safety-rated applications should note that relay contacts in the DSQC 653 are standard outputs, not safety-rated contacts. For safety-critical switching (e.g., guarding, enabling circuits), the IRC5’s dedicated safety I/O system should be used rather than the DSQC 653.
DSQC 653 vs. DSQC 652 — Choosing the Right Module
The choice between the DSQC 653 and the DSQC 652 depends entirely on the load characteristics and electrical environment of the application. The DSQC 652 (solid-state) is faster, has no mechanical wear, and handles high-frequency switching applications. The DSQC 653 (relay) provides full galvanic isolation, handles loads at different voltages, and is appropriate for lower-frequency switching of inductive loads.
Relay contacts are subject to mechanical wear — the DSQC 653 has a finite contact life measured in switching cycles. In applications requiring very frequent output switching (more than several times per second sustained), the DSQC 652’s solid-state outputs will significantly outlast the DSQC 653’s relay contacts. For typical robot cell applications with infrequent output switching, relay contact life is rarely a limiting factor.
When replacing a failed DSQC 653, always check whether the relay contacts failed open (load never activates) or closed (load always on) — this determines whether the replacement is urgent from a safety perspective. A relay welded closed can present a safety hazard if the output controls a safety-relevant function.
Frequently Asked Questions
Q: Can the DSQC 653 relay outputs switch 230V AC loads directly?
A: The relay contacts in the DSQC 653 provide galvanic isolation from the IRC5 24V DC control circuit, which means they can in principle switch loads at different voltages including 230V AC. However, the exact voltage and current rating of the relay contacts must be verified against the ABB product documentation and the specific IRC5 variant before connecting mains-voltage loads. Do not assume AC switching capability without confirming the relay contact specification — contact ABB or Atlantech Drives for technical confirmation before wiring.
Q: What is the key difference between the DSQC 653 and the DSQC 652?
A: The DSQC 652 (3HAC025917-001) has solid-state transistor outputs — fast, wear-free, but limited to 24V DC loads in the same voltage domain as the IRC5. The DSQC 653 (3HAC025918-001) has electromechanical relay outputs — fully galvanically isolated, capable of switching loads at different voltages, but subject to mechanical wear and slower switching. The DSQC 652 has 16 inputs and 16 outputs; the DSQC 653 has 8 inputs and 8 relay outputs.
Q: After a DSQC 653 output relay fails, does the contact fail open or closed?
A: Relay contact failure mode depends on the failure mechanism. Contacts can fail open (most common — contact erosion or spring failure) or fail welded closed (less common — caused by excessive current at the moment of switching). Identify the failure mode before assuming the replacement is safe — a relay welded closed on an output controlling a motion or safety function requires immediate attention regardless of whether the robot program commands the output off.
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