Atlas Copco 1622503080 (1080424154) 55kW Motor Assembly for GA Series Screw Compressors

The Drive Motor's Position in a Screw Compressor

The main drive motor is the power heart of any rotary screw compressor. It converts three-phase electrical energy into the mechanical torque that spins the compressor air end. In a 55kW-class machine, this component determines the system's air delivery capability, energy consumption, and long-term reliability. The Atlas Copco 1622503080 motor assembly is purpose-engineered for this role in GA55, GA55+, and GX55 oil-injected compressor platforms.

This is not an off-the-shelf industrial motor adapted to fit. Atlas Copco designs the 1622503080 as part of the complete compressor system. The shaft dimensions, mounting flange, bearing selection, and thermal characteristics are all matched to the air end coupling and compressor frame. This integrated engineering approach ensures proper alignment, smooth torque transmission, and vibration-free operation throughout the motor's service life.

Part Number History: 1080424154 Becomes 1622503080

Within the Atlas Copco parts system, 1622503080 is the current active part number for this 55kW motor assembly. The number 1080424154 is a previous system reference that identifies the same component. Atlas Copco renumbered the part during a system update. Both numbers refer to the identical motor assembly with no change in dimensions, specifications, or performance characteristics.

When ordering a replacement, you can reference either 1622503080 or 1080424154. An authorized distributor or the Atlas Copco parts portal will map both to the same physical unit. This is useful for maintenance teams who may find either number on an existing machine's nameplate. It also appears in older service documentation.

The 1622503080 motor is designed for continuous S1 duty. This means it can run at full rated load without interruption, a requirement for production air compressors that operate around the clock in manufacturing plants. The motor's thermal design manages the heat generated by sustained 55 kW output. Class F and H insulation materials in the stator windings provide a wide thermal safety margin above the normal operating temperature.

The IP55 enclosure protection rating means the motor housing is dust-protected and resistant to water jets from any direction. This level of ingress protection suits the compressor canopy environment. Dust from the intake filtration system and ambient factory air particles are typical inside a compressor canopy. Occasional wash-down cleaning does not compromise the motor's internal integrity.

Atlas Copco supplies this motor as a complete MOTOR ASS'Y, not as a bare motor unit. The assembly includes the mounting base, coupling flange, terminal box, and all structural interfaces ready for direct installation into the compressor frame. This ensures the shaft centre height, bolt pattern, and coupling position align precisely with the manufacturer's air end mounting specification.

During replacement, maintenance teams should note a specific installation requirement. The original spacer and bolt hardware on certain compressor configurations must be replaced with stud 1630 0600 28. This hardware update improves clamping consistency and is documented in Atlas Copco service bulletins for 55 kW motor replacements.