Enough single vs 3 ph,, it isn't answering the original question. You will find that most compressors that require more than 20A or more than 115V are going to be set up for "hardwiring". This is simply a matter of reducing costs and liability insurance for the manufacturer, plus most 220V compressors are too large to be "portable" so hardwiring makes sense and is marginally safer. The choice of actually hardwiring it or adding an appropriate size plug is up to you. If you decide to add a plug, make sure it is of an appropriate size, 220V plugs come in several amp ratings each with a unique prong arrangement. To determine which you need, there should be an electrical rating plate somewhere on the unit that gives the motor draw amps. If you want to use an existing outlet, make sure it is wired for enough capacity, never swap a 220 outlet for one of a higher rating! If you are needing to run a new circuit for the compressor and/or are not comfortable working with 220V, find a friend who is and is knowledgeable, or call in an electrician, The cost to have a pro do the connection will not be high if you locate the compressor close to the service panel.

Let's talk a minute about what happened to your previous compressor. You said it got wet in the rain? Was it installed outside without being weather protected? An electric motor getting wet should not destroy it unless it is running at the time or is turned on while still soaked, but even then it would likely blow the circuit breaker or trip an overload switch on the unit, But it still is not a good idea to just put it outside without some basic weather protection. A basic prefabbed garden tool shed erected around it would have sufficed and been a lot cheaper than a new compressor! I hope you are planning on installing this one inside or protected???

Here is a hint: to reduce the running noise dramatically and keep the compressor from "walking" from it's vibrations on a concrete floor or pad: drill a set of hockey pucks for a recessed carriage bolt and bolt to the bottom of the feet, Use a 5/8 or 3/4" spade bit to drill 1/2 way thru the puck then finish the center hole with a twist bit sized to your bolt. You will find you can drill the puck as easily and cleanly as drilling wood.

 

Here is the installation manual for the compressor. It says it is indeed single phase. Also says it must be bolted to the ground (anchored), and it includes a typical air distribution diagram.

http://www.mikestools.com/download/D...l-D26161-E.pdf

AX, I wouldn't put it in a shed, it needs plenty of air for cooling. A simple roof would be fine.

It looks like a nice unit!

 

Ross, I typically prefer to err on the conservative side, but I stand behind putting the compressor in a garden tool shed (assuming using a stand up height shed). They are usually a minimum of 4' square. Those things are far from air tight, and the typical home shop use of a compressor of this size is low. If he is going to use the compressor for an extended length of time at a high enough draw to run the compressor near it's duty cycle (50% according to the manual) Then he can simply open the door for more cooling air and/or add an exhaust fan near the top of one wall wired to come on with the compressor and a filtered intake low on the opposite wall. I really wouldn't want my compressor sitting out in the open exposed to all the typical airborn dirt and dust 24/7.
I have a very similar compressor, mine also recommended anchoring. If you set the metal feet on a concrete floor the unit will "walk" and could rip out the electrical and/or air supply connection or fall over if bumped hard enough. I have never had mine move even a fraction of an inch with the hockey pucks, even tho my floor is extra smooth and coated, and if concerned with it falling over then a simple chain, cable, or strap tether to the wall will solve that risk.

By the way if that manual is for the right model, it's a 2 stage compressor, a nice unit that would typically retail in the 1200.00+ range, and easily handle most any home shop compressed air need.

 

I have a 7hp, 60 gal. air compressor in my shop. It runs off of 220 single phase. It came with a plug on the end of the cord so I wired a compatible outlet on the wall. I also have a timer set up on it the even something in the airline gives during the night, I don't want the compressor running all night. I have the timer set at 9 hours, I turn the system on first thing in the morning . I usually turn the power off via the timer box which I have a ON/OFF switch but some times I forget.

I also have the tank connected to the piping on the wall via a ball valve with a hydraulic hose. The hose allows for vibration and flexing between the compressor I have left mounted on the original pallet and the hard pipe on the wall.

I have a MIG welder and plasma cutter also wired into the breaker box on a separate breaker so I don't have to worry if the air compressor kicks on while using either the welder or plasma cutter. I know the compressor going to run with the plasma cutter because I need air for the plasma cutter. If I had them both the same circuit the breaker would always blow. The plasma cutter and welder I have hooked up, via a double box extension cord because I never use them both simultaneously.

 

I have a 5hp, 2 stage compressor with a 3 cylinder pump and a 60 gallon tank. I hardwired it and did not bolt it to the floor. I did bolt a 2x4 frame to it and placed it on a 1/2" thick rubber pad. It hasn't moved in the 4 years that it has been there. I also used the link belt system which lessens the vibration and slippage.