Great score Mark. I didn't know you could buy 10HP in single PH. Learn something everyday.
The 10HP Single Phase units are not common. Most of the 10HP units are 3-phase. Commonly these compressors are used in Commercial applications such as shops and businesses where 3-phase is readily available. The most important thing for the single-phase motor is to have an appropriately sized circuit breaker, wire gauge, Magnetic Starter switch, and thermal overload protection. I will have to run 3 conductors (Red/Black/Green) of 6 gauge wire in metal conduit to the compressor. For air distribution, I will install black-iron 1" pipe back into my work shop. It will probably cost about $500 in the wire, pipe, and start switch just to get the system installed properly. I think that 10HP is probably the largest system you can run on Single phase 220.
Unfortunately, it has been common practice for air-compressor manufacturers to over-inflate their capacity numbers and misrepresent their product so they can have a competitive advantage. Sometimes a motor marked at 10HP is really 7.5HP...etc. You can look at the motor tag and do some calculations to determine if the motor is really rated as advertised. The Marathon motor on my new compressor is truly 10HP at the output shaft. This is done by calculating the Watts (Volts x Amperes). Then Convert to Horse Power (Watts / 746). Then multiply the Horse Power by an efficiency factor (HP x FLEF). This gives you the true output shaft HP.
Edited by markdombroski, February 08, 2013 - 07:22 PM.