Atlas Copco GA 18 VSD (FF VSD⁺) Oil-injected Air Compressor

The Atlas Copco GA 18 VSD pairs an 18 kW (25 hp) motor with an integrated variable speed drive. The family spans two branches: the current machine with an iPM permanent magnet motor and Neos Next inverter, and the earlier GA 18 VSD+ build on the WorkPlace frame. Pack and Full Feature supply applies where the table lists two weights. Because the converter synthesizes its own motor frequency, the published performance applies to 50 Hz and 60 Hz plants in one table per branch. Maximum working pressure for the family is 13 bar(e).

Factory variants span 4, 7, 10, and 12.5 bar on the current build, so the GA 18 VSD serves low-pressure processes and high-pressure tools from a single network. The drive accelerates the motor without current peaks and allows a restart into a pressurized line.

Especificações técnicas

Performance is measured according to ISO 1217, Edition 4:2009, and the same capacity envelope holds for both supply frequencies. The current GA 18 VSD iPM carries a permanent magnet motor on a vertical frame.

Every variant runs on the same 18 kW (25 hp) motor. The machine weighs 276 kg and stands 978 mm long, 695 mm wide, and 1473 mm high. The mean noise level reads 70 dB(A) at one meter, and the maximum working pressure prints at 13 bar(e).

The GA 18 VSD+ Branch

The earlier GA 18 VSD+ build carries the same 18 kW (25 hp) rating, with a 13 bar(e) (188 psig) maximum working pressure. Four variants cover 4, 7, 9.5, and 12.5 bar. Its mean noise level reads 67 dB(A), measured at one meter at maximum working pressure according to ISO 2151 and ISO 9614-2.

Capacity is referenced to ISO 1217, Annex E, with FAD measured at 4, 7, 9.5, and 12.5 bar(e) effective working pressures. The WorkPlace package weighs 367 kg and the Full Feature build 480 kg. The frame of the GA 18-37 VSD+ group stands 1590 mm high on a 780 mm long base, at 811 mm wide as a standard build and 1273 mm deep with the Full Feature dryer module in place.

Drive Train and Inverter

The current GA 18 VSD drives the element through an IP66-protected drive train with an oil-cooled iPM motor that equals IE5 motor efficiency standards. No gears or belts means no transmission losses. The Neos Next inverter combines the functionality of an entire electrical cubicle in one compact unit and carries an IP54 rating against dust and dirt. Together with the motor it exceeds the IES2 requirements for power drive efficiency.

Soft acceleration spares the electrical infrastructure, and a restart into a pressurized network needs no depressurizing procedure. The Elektronikon Touch controller supervises compressor and drive together, with warning indications, shutdown handling, and maintenance scheduling.

Turning Down to a Trickle

On the 7 bar variant the GA 18 VSD modulates from 11.8 l/s up to 58.3 l/s (25 to 123 cfm) as the plant breathes. That is a turn-down of close to five to one. A fixed speed unit below its load point has to blow the surplus to atmosphere, spending power on air nobody uses. The variable speed machine simply slows the element and rides the demand curve instead.

Network pressure stays inside a narrow band across the whole operating range. Downstream equipment sees a steady supply, and the safety margin that plants normally hold against fluctuations can shrink. Fewer load and unload cycles also ease wear on the element, the motor, and the switchgear.

Air Path and the Full Feature Build

Intake air passes the inlet filter and the intake valve before reaching the screw element. An air/oil separation vessel, minimum pressure valve, and aftercooler complete the circuit, with a water separator and drain handling the condensate. Options extend the package with a heavy duty inlet filter, pre-filter, DD and UD+ filtration, and dryer bypass.

The Full Feature build carries an integrated refrigerant dryer with all wiring and piping completed in the factory and tested as one unit before dispatch. On the GA 18 VSD+ branch the dryer extends the frame depth from 811 to 1273 mm within the same footprint, so no field plumbing between compressor and treatment equipment is needed.

Where the GA 18 VSD Fits

Plants whose air draw moves between shifts, batches, or seasons gain the most from the GA 18 VSD. Every minute of avoided unloaded running shows up directly on the power bill. The vertical build parks against a wall or at the point of use, and mixed-pressure sites can consolidate two fixed speed units into one machine. For level, full-load duties the fixed speed Atlas Copco GA 22 Oil-injected Air Compressor one step up remains the natural choice.

GA 18 VSD FAQ

Why is there a single table per branch for 50 Hz and 60 Hz?

The drive creates its own motor frequency, so element speed does not follow the grid, and one capacity envelope measured per ISO 1217 serves both supplies.

How far can output turn down?

On the 7 bar build of the current machine flow modulates from 11.8 to 58.3 l/s (25 to 123 cfm). The 4 bar build reaches 58.6 l/s (124 cfm) at the top of its envelope.

What separates the current machine from the GA 18 VSD+?

The current build carries an iPM motor and Neos Next inverter, reads 70 dB(A), and weighs 276 kg. The GA 18 VSD+ is the earlier platform at 67 dB(A), with WorkPlace packages from 367 kg and a 9.5 bar variant step.

Which branch suits a site that orders the dryer separately?

The GA 18 VSD iPM build at 276 kg suits export projects and point-of-use installations where air treatment is specified apart. The GA 18 VSD+ Full Feature form integrates the dryer on its own 1273 mm deep frame.

How efficient is the motor?

The oil-cooled iPM motor equals IE5 motor efficiency standards, and the drive train is IP66 protected with no gears or belts to introduce transmission losses.

What pressures does the family cover?

The current build spans 4, 7, 10, and 12.5 bar variants, while the GA 18 VSD+ covers 4, 7, 9.5, and 12.5 bar. Maximum working pressure is 13 bar(e) across the family.