Either an electrical problem, or the compressor has tripped on a safety device. Check supply power. Check for errors on display. Check emergency stop is out. Check and reset the overload relay. If it’s a new installation, check the phase sequence. Ambient temperature too high or not enough ventilation.
[pdf] 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. If the voltage drop significantly when the compressor starts/runs, you have a bad connection somewhere. Check all relays, fuses and electrical connections.
[pdf] One of the most common ways to check if your air compressor tank is leaking air is to hear it closely. Try implementing a system in which someone will walk close to the tank and search for any hissing nois.
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