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. If the voltage drop significantly when the compressor starts/runs, you have a bad connection somewhere.
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[pdf] To connect two compressors in parallel, follow these steps: Make sure both compressors have the same voltage and phase. Install a check valve on each compressor’s discharge line to prevent backflow. Install a tee fitting on each compressor’s discharge line. Connect the two tee fittings with a pipe..
To connect two compressors in parallel, follow these steps: Make sure both compressors have the same voltage and phase. Install a check valve on each compressor’s discharge line to prevent backflow. Install a tee fitting on each compressor’s discharge line. Connect the two tee fittings with a pipe..
The Short Answer: The basic process involves setting up a single pressure switch system linking both compressors, using a check valve to prevent air backflow, and using suitable hoses or pipes.
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