If the capacity of the air compressor is really too low, check the following: Check differential pressure over oil separator. Replace separator when necessary. Check and replace compressed air filters (if installed). Compressor does not unload. Check if pressure switch is correctly set and working.
[pdf] Motor Power: 22KW to 250KW | 30HP to 335 HP Working Pressure:3 – 5 Bar | 0.3Mpa to 0.5Mpa Free Air Delivery (FAD): 2.74 to 64.54m³/min | 95 to 2280 CFM Delivers efficient, space-saving performance with integrated storage for continuous, reliable air supply.
[pdf] It should turn around smoothly, without any 'hickups' (be sure to completely shut down the air compressor!). Check the isolation of the motor windings. Should be in the mage-ohms (you need an isolation tester / high voltage ohm meter for this). Check the voltage when the compressor is running.
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