Compressor Duty Calculation

What does the duty cycle of an air compressor mean?
The duty cycle of an air compressor is the ratio of the time it produces air to the time it is stationary. For example, if an air compressor runs at a 60% duty cycle for one minute, the compressor is compressing air for 36 seconds and is stationary or idling for 24 seconds. Expressed as a percentage, the number of seconds represented by this number can be subtracted from the total cycle time. The total cycle time is the time it takes the compressor to complete a full load and unload cycle.

Piston air compressors are usually expressed as a percentage; other types of compressors such as rotary compressors and screw compressors also have a duty cycle. When the pressure drops to a certain set point, the compressor will run and continue to compress air until the maximum set pressure is reached.

A complete cycle is the time it takes to use and fill the air compressor's air tank. When calculating the duty cycle, the calculation of the air compressor's running time needs to take into account the compressor's downtime.

Calculation for air compressor duty cycle:
Compressor running time / (running time + rest time) = duty cycle percentage

Air compressor duty cycle calculation example
50% air compressor duty cycle calculation: Assuming the air compressor cycles for two minutes, 60 seconds of pressurized air can be drawn from the machine. You must wait another 60 seconds to get air power again.

How long can an air compressor run continuously?
Reciprocating air compressors are difficult to run continuously. When your workshop is running 24 hours a day, oil-free screw air compressors are an option. Oil-free screw air compressors do not require interval cooling like reciprocating air compressors.

What is the cycle frequency of the compressor?
The number of cycles of the air compressor affects the efficiency of the air compression system. If the recommended duty cycle frequency is exceeded, the air compressor will wear out faster. The number of cycles of the compressor depends on the machine's cycle time and rated duty cycle time. The faster the air compressor cycles, the higher the energy consumption. Longer cycle times can increase the service life of the air compressor.

Ways to extend the cycle time
1. Use a larger air storage tank.
2. Reduce the pressure between the main air storage tank and the compressor.