Atlas Copco GA 37 VSD (FF VSD⁺) Oil-injected Air Compressor

The Atlas Copco GA 37 VSD opens the GA 37-90 VSD series, pairing a 37 kW (50 hp) motor with an integrated variable speed drive. The family runs in two branches: the base machine and the newer GA 37 VSD+ build. 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. Maximum working pressure for VSD machines is 13 bar(e) (188 psig).

Factory variants span 4, 7, 10, and 13 bar on the base branch, so one machine can serve 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.

Technical Specifications

Performance is measured according to ISO 1217, Annex E, Edition 4:2009, and the same capacity envelope holds for both supply frequencies.

Every variant runs on the same 37 kW (50 hp) motor. The WorkPlace package weighs 1042 kg (2297 lb) and the Full Feature build 1127 kg (2485 lb). The footprint measures 1766 mm wide, 970 mm deep, and 1800 mm high, a mid-size frame shared across the GA 37-90 VSD series.

The GA 37 VSD+ Branch

The newer GA 37 VSD+ build carries the same 37 kW (50 hp) rating with a 13 bar(e) 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. The Pack measures 1100 mm deep, 1153 mm wide, and 1968 mm high. The Full Feature build keeps depth and height but widens to 1656 mm, because the dryer module rides beside the compressor on the shared frame instead of behind it. At 860 kg (1060 kg with Full Feature) the branch trims 182 kg off the base package while adding top-end flow.

Turning Down to Quarter Load

On the 7 bar variant the base machine modulates from 26.0 l/s up to 123 l/s (55 to 260 cfm) as the plant breathes, a turn-down 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.

Drive and Control

The converter sits inside the canopy with its own cooling loop and is EMC tested to keep emissions inside industrial limits. Soft acceleration spares the electrical infrastructure, and a restart into a pressurized network needs no depressurizing procedure. The drive concept is common to every VSD build in the series, so a crew trained on one machine can service the others without retraining.

The Elektronikon controller supervises compressor and drive together. It holds every operating point inside safe parameters, schedules service by real running hours, and reports alarms in plain language so the crew can act without decoding fault codes.

Air Path and the Full Feature Build

Intake air passes a heavy duty filter that captures 99.9% of particles down to 3 microns before reaching the element. A 3-step separation stage holds residual oil content below 3 ppm, and an integrated water separator with electronic drain clears condensate from the circuit. This path is identical across the GA 37 VSD branches, so air quality figures carry over from one build to the next.

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. No field plumbing between compressor and treatment equipment is needed, and the finished package matches the 1127 kg figure in the table above.

Where the GA 37 VSD Fits

Plants whose air draw moves between shifts, batches, or seasons gain the most, since every minute of avoided unloaded running shows up directly on the power bill. Mixed-pressure sites can consolidate two fixed speed units into one machine that covers blowing in the morning and tooling after lunch. For level, full-load duties the fixed speed Atlas Copco GA 250 Oil-injected Air Compressor range and the GA 37 remain the natural choices.

GA 37 VSD FAQ

Why is there a single table 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, Annex E serves both supplies.

How far can output turn down?

On the 7 bar build flow modulates from 26.0 to 123 l/s (55 to 260 cfm); the 4 bar build spans 26.0 to 124 l/s (55 to 263 cfm).

What separates the base branch from the GA 37 VSD+?

Both carry 37 kW (50 hp) and a 13 bar(e) maximum. The base machine covers 4 to 13 bar at 66/67 dB(A) on a 1042 kg package. The GA 37 VSD+ covers 4 to 12.5 bar at 67 dB(A), starting at 860 kg and 1100 mm deep.

Which build for pressures above 12.5 bar?

The base branch, since its variants reach 13 bar. The VSD+ tops out at 12.5 bar but answers with a lighter package and the newer platform.

How heavy is the machine?

The base WorkPlace package weighs 1042 kg and the Full Feature build 1127 kg. The VSD+ branch weighs 860 kg as a Pack and 1060 kg with Full Feature.

What does the Full Feature build include?

An integrated refrigerant dryer with factory wiring and piping, filtration, and electronic condensate drains, delivered tested as one unit. On the VSD+ build the dryer widens the package from 1153 to 1656 mm instead of lengthening it.