Try to turn the compressor by hand. It should be possible to turn it around. It should turn around smoothly, without any 'hickups' (be sure to completely shut down the air compressor!). Check the isolation of the motor windings.
[pdf] Driven pile and helical or screw pile foundations are good alternatives that have been used successfully, even for very large reciprocating compressor packages. A pile foundation has the advantage of lower costs and shorter installation time compared to concrete block foundations.
[pdf] The Variable Frequency Rotary Screw Air Compressor is an energy efficient solution for industrial air compression requirements. The motor output frequency is intelligently matched to air consumption, making it more energy efficient and longer lasting than traditional air compressors.
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