Heidelberg Windmill 1 or 3 phase

Hi printers, I’ve located a 12x18 Windmill which I am interested in purchasing. The owner is 80 years old and can’t recall if its on a single phase or 3 phase motor. Is there any way I can physically identify which one it is.

If I powered a 3 phase motor on a single phase outlet, would it run? Just wondering, maybe I can go by a process of elimination.



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If single motor, make sure you have it on a single line with decent breaker. If 3 phase, have an electrician install a 220 Line , use a static converter to get 3 phase and run it.
(eg: Anderson converters).

I don’t know you’d have much luck identifying a single phase from 3 phase without looking at the motor plate. Any motor should be designated PH 1 or PH 3.


HI Omar,
My Windmill had 3 phase, it was a very thick orange cable that led from the motor. If you google 3 phase power point and look at the images you will see that it’s not an ordinary power point. It’s a large box with a large on/off dial and has 4 straight round plug points.


I googled “3 phase power point” as you suggested, and I see what you are referring to. Is the “power point” the technical term for a wall outlet? When i asked the owner if it had a single phase or 3 phase motor, he didn’t know, and said it had a 3 prong plug.

Does a 3 prong plug = single phase motor?


Single Phase 220 would be a three-prong plug. Two-“hot” wires and a ground.

Three phase would be a four-prong plug (three-phases and a ground), or a five prong plug (three-phases, a neutral, and a ground) depending on if it were wye or delta.

On the Plug, if the Blades are parallel ( I I ), it’s single Phase, if one Blade is horizontal ( I — ) it’s 220.


Are you saying that a plug can not be single phase and 220v at the same time? I see that Philipmat1 identifies a 3 prong plug as single phase and 220v.


The three pin grounded plugs with blades parallel ( | | )are for 120V, which is as far as I know all single phase. I am pretty sure that NEMA code requires a different plug and outlet for 220/230/240 volt single phase, which I believe can either be with the two blades perpendicular to each other or in a straight line - - . With three phase there are more wires and I don’t think there is a standard plug for that — I’m pretty sure three phase must be direct-connected. Correct me if I am wrong if you are a qualified electrician. Of course anything can be home-brewed — you could wire a standard grounded outlet to 220, but woe be unto you if you plug a standard 120V appliance into it!


My Platemaker is 240 single Phase, the plug has 4 Blades, instead of guessing I would eg use Mc Master or Grainger, look up the specs for the Plugs and recepticals , print it out even and compare to what is on your windmill. Most Windmill motors run 110 or 220 or 3 phase. 110 / 220 can be done with a Plug, 3 phase by Code is always hardwired. I don’t know there you are, but if my electric is not up to snuff, aside from fines and what not, I automatically loose my business license and need to come up with a huge bond for re applying.

Yep. NEC (National Electrical Code) requires different plugs for 120 and 220 equipment. It does allow for plugs on three phase equipment (you can get five bladed plugs).

Normal household power is 240/120 split phase. You get three wires from the power company, Line-Neutral-Line. From Line-to-Line you will measure 240V and Line-to-Neutral gives you 120V. The Neutral is bonded to ground at the service entrance.

A three bladed plug can be either 240 or 120 single phase, depending on the orientation of the blades. Four-bladed plugs can be either single phase or three phase. Three phase will be four blades and higher.