There are a number of factors to consider when selecting an air compressor that will best suit your needs. One of these is whether a fixed-speed or variable-speed air compressor will be the best solution for your application. So, what exactly is the difference?
Variable-Speed Rotary Screw Compressors
Variable-speed compressors maintain a constant air pressure and the motor speed will be adjusted to meet the air demand of your production. Variable-speed compressor units can run on 100% flow or can fluctuate to less flow to conserve energy and align with the current air demand.
The benefits of a variable-speed air compressor are:
- Reduced energy consumption (in the proper application)
- Quieter than a fixed-speed compressor when running at a lower RPM
- Consistent plant pressure
- Increased component lifetime
- Low inrush current during motor starts
- May qualify for energy incentives
Fixed Speed Rotary Screw Compressor
Fixed-speed compressors run either full throttle or are switched off. These are ideal in applications where there is a constant compressed air demand 24/7. The machine will run at a constant RPM unless turned off. The inlet valve will flutter based on when air is needed or not needed instead of ramping the engine up and down.
The benefits of a variable-speed air compressor are:
- Lower capital cost
- Increased parts availability
- Lower maintenance and repair costs
- More efficient in applications with a consistent demand
Source: Chicago Pneumatic Australia (link to https://www.cp.com/en-au)