ABB IRB7600 AC Servo Motors: 3HAC036646-002 / 3HAC036644-002 / 3HAC025819-003

Technical Dossier

Product Details And Specifications

ABB IRB7600 Series: Comprehensive AC Servo Motor Range and Technical Overview

The ABB IRB7600 is a heavy-duty industrial robot arm platform deployed across global heavy industry sectors including petrochemical plants, nuclear facility maintenance, offshore oil refinery automation, automotive body-in-white assembly, and large-scale metal fabrication. With payload capacities ranging from 150 kg to 500 kg and a reach envelope of up to 3.5 m, the IRB7600 occupies the highest tier of ABB's IRB robot family. Its servo motor subsystem — comprising axis motors, resolvers, and associated drive components — is a critical maintenance category for facilities operating this platform beyond its standard 10-year service cycle. The three SKUs covered on this page (3HAC036646-002, 3HAC036644-002, 3HAC025819-003) are axis-specific AC servo motors used in the IRB7600 mechanical unit and are classified as ABB Robotics spare parts under the 3HAC (Robotics Hardware Component) numbering convention.

The Evolution of IRB7600 Architecture

The IRB7600 platform was introduced by ABB in the early 2000s as a successor to the IRB6400 and IRB7500 heavy-payload lines. Its servo motor architecture has evolved across three distinct hardware generations:

Generation 1 (IRC5 controller, pre-2008): Early IRB7600 units used resolver-based servo motors with analog feedback. These motors are identified by 3HAC part numbers in the 3HAC0xxxxx range and are now fully discontinued by ABB. Replacement requires cross-referencing with updated 3HAC02xxxxx or 3HAC03xxxxx equivalents.

Generation 2 (IRC5 controller, 2008–2016): Revised motor specifications introduced improved thermal management and updated encoder interfaces. The 3HAC025819-003 falls within this generation. Compatibility with Generation 1 mechanical housings requires verification of flange dimensions and connector pinout.

Generation 3 (IRC5 / OmniCore transition, 2016–present): ABB introduced OmniCore controller compatibility alongside updated servo motor variants. The 3HAC036646-002 and 3HAC036644-002 are associated with this generation. These motors feature updated resolver-to-digital converter interfaces and revised cable harness connectors (3HAC044168-001 series).

Cross-generation compatibility is not guaranteed. Axis assignment (Axis 1 through Axis 6) must be confirmed against the robot's mechanical unit serial number and the ABB Spare Parts Catalog revision applicable to that unit's manufacturing date.

IRB7600 Full Catalog & Functionalities (SKU List)

The following SKUs represent the verified AC servo motor and associated drive component range for the ABB IRB7600 mechanical unit. Each entry reflects a distinct axis assignment or hardware revision.

3HAC036646-002: Axis motor unit, IRB7600 — primary axis drive, Generation 3 specification, resolver feedback interface.
3HAC036644-002: Axis motor unit, IRB7600 — secondary axis assignment, matched pair configuration with 3HAC036646-002.
3HAC025819-003: AC servo motor, IRB7600 — Generation 2 specification, used in mid-production mechanical units, resolver-based feedback.
3HAC025817-001: Servo motor, Axis 1, IRB7600 — high-torque base rotation drive, flange mount type A.
3HAC025818-001: Servo motor, Axis 2, IRB7600 — lower arm drive, integrated thermal protection.
3HAC025820-001: Servo motor, Axis 3, IRB7600 — upper arm drive, compact form factor variant.
3HAC025821-001: Servo motor, Axis 4, IRB7600 — wrist rotation primary, resolver type B.
3HAC025822-001: Servo motor, Axis 5, IRB7600 — wrist bend drive, low-inertia specification.
3HAC025823-001: Servo motor, Axis 6, IRB7600 — tool flange rotation, high-speed variant.
3HAC036640-001: Motor cable assembly, IRB7600 — axis 1–3 harness, 7 m standard length.
3HAC036641-001: Motor cable assembly, IRB7600 — axis 4–6 harness, upper arm routing.
3HAC044168-001: Resolver cable, IRB7600 — Generation 3 feedback wiring, M23 connector.
3HAC026253-001: Brake unit, IRB7600 — axis 1 holding brake, 24 VDC actuation.
3HAC026254-001: Brake unit, IRB7600 — axis 2/3 shared brake assembly.
3HAC036648-001: Motor mounting kit, IRB7600 — axis replacement hardware set, includes torque bolts.
3HAC025816-001: Encoder interface board, IRB7600 — resolver signal conditioning, DIN rail mount.
3HAC036643-001: Axis computer unit, IRB7600 — IRC5 drive interface, axis 1–3 control.
3HAC036645-001: Axis computer unit, IRB7600 — IRC5 drive interface, axis 4–6 control.

Sourcing Hard-to-Find & Obsolete IRB7600 Parts

ABB has progressively discontinued spare parts support for IRB7600 units manufactured before 2012. The 3HAC025819-003 and related Generation 2 motor variants are no longer listed in ABB's active spare parts catalog as of 2023. DriveKNMS maintains a dedicated inventory of new-old-stock (NOS), refurbished, and functionally equivalent servo motor units for the IRB7600 platform, sourced through authorized surplus channels and OEM-certified refurbishment partners.

For facilities operating IRB7600 robots under long-term maintenance contracts — particularly in nuclear, chemical, and offshore environments where robot replacement is operationally impractical — DriveKNMS provides lifecycle extension support including: verified cross-reference mapping between discontinued and current part numbers; functional testing against ABB's original motor performance specifications; and documentation packages suitable for maintenance record compliance.

Lead times for obsolete IRB7600 servo motors vary by axis assignment and hardware generation. Contact DriveKNMS with your robot serial number and axis fault code for a targeted sourcing assessment.

Quality Control for the IRB7600 Range

IRB7600 servo motors present specific test challenges due to the platform's high-torque axis architecture and resolver-based feedback system. DriveKNMS applies the following test protocol to all IRB7600 motor units prior to dispatch:

Resolver signal verification: Each motor is connected to a calibrated resolver-to-digital converter (RDC) test bench. Sine/cosine output amplitude, phase angle, and null voltage are measured against ABB's published resolver specification for the applicable 3HAC part number. Units with resolver null voltage exceeding 15 mV are rejected.

Winding resistance and insulation test: Phase-to-phase resistance is measured with a precision milliohm meter. Insulation resistance between windings and motor frame is tested at 500 VDC using a Megger instrument; minimum acceptable value is 100 MΩ.

Bearing inspection: Motors are rotated by hand and under low-speed motorized drive to detect bearing roughness, axial play, and radial runout. Bearings exhibiting audible defects or runout exceeding 0.02 mm are replaced prior to dispatch.

Brake function test: For motors with integrated holding brakes, brake engagement and release are verified at 24 VDC nominal. Brake torque is confirmed against the axis-specific holding torque specification.

Connector and cable inspection: All motor connectors are inspected for pin corrosion, bent contacts, and seal integrity. Cable jackets are inspected for cracking, abrasion, and continuity.

Test records are retained for each unit and are available upon request for maintenance documentation purposes.