How to Wire a 220 Air Compressorby K.K. Lowell
An air compressor is arguably the handiest tool in a repair shop. Air compressors can run air tools and spray paint, not to mention supplying air to inflate tires and toys. Even a small compressor is a worthwhile addition to the home shop, but the greatest versatility comes with larger compressors that can supply more cubic feet per minute. A very popular home shop compressor is the 5 HP vertical with a 60-gallon storage tank. These compressors are powered by 220 volts and are generally hard-wired.
Place the compressor as close to the circuit breaker box as possible, in an area where it can be easily accessed. Bolt it to the floor with anchors and lag bolts.
Shut off the main circuit breaker. Remove the cover from the fuse box and install a 30-amp 220-volt circuit breaker for the compressor. Run the 10-gauge 3-conductor wire into the box. Connect the red and black wires to the circuit breaker terminals, and the white and bare copper wires to the ground bus. There may be two ground busses in the box---if so, connect the bare copper wire to one and the insulated white wire to the other.
Secure the 10-gauge wire to the wall according to your local codes and run it to a junction box near the compressor. The connection from the compressor to this box must be made with 10/3 flexible power cord. Run a length of this wire from the switch box of the compressor to the junction box. Connect to the wire from the circuit breaker box. Make the connections between the two wire types using large wire nuts.
Remove the cover of the compressor switch box and connect the 10/3 power cord to the marked terminals. Use solderless ring connectors to make the connections.
Restore the power to the main circuit breaker.
- Don't forget that electricity can kill. Use extreme care when doing this project. If you are not totally confident in your ability to do this work, consult a qualified electrician.