Try to turn the compressor by hand. It should be possible to turn it around. It should turn around smoothly, without any ‘hiccups’ (be sure to completely shut down the air compressor!). Check the isolation of the motor winding.
[pdf] According to screw compressor manufacturers, treatment is closing the ball valve to verify that the rated pressure can be attained and inspecting the air compressor component to prevent issues with that component constituting the treatment procedure.
[pdf] Compressor air screw VSDs usually have noise levels ranging from 60 dB to 85 dB, depending on the factors mentioned above. When selecting a compressor, it's important to consider the acceptable noise level for your specific application.
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