Making a 3 Phase Motor Work

I’ve tried reading some posts on this topic, but I’m still not sure of the best solution, especially for various equipment.

I have the opportunity to get a C&P Craftsman Power Cutter for an extremely low price. The only problem is that it’s currently on a 3 phase motor that the owner says requires 440-600V. I only have your typical single phase electricity available.

What are the options for making this work and is it worth it or not (considering the cutter is almost free!)?


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That sounds like a lot of voltage even for 3-Phase. Usually printing equipment, and especially a cutter, will work on 240 volts 3-Phase. HOWEVER, if you don’t have it, there is no practical way to get it, absent the power company bringing in the lines.

Even if 3-phase is running on the poles right outside your front door, a 3-phase drop and panel will cost you an arm and a leg, plus 2 licensed electricians for about 4 hours work. The labor alone will run $250 to $300 and the power company fee probably $600. Next you have the panel, switches and fuses for another $400.

Now I haven’t had to mess with 3-phase power since I sold my last print shop building back in 1986, and perhaps they’ve worked some magic since then. If not, that “free” cutter is going to cost you at least $1500 and that’s assuming you only need 240 volts and the power is already on the closest pole to your location.

If you do have to go up to 440-480 volts (which seems absurd) then at least double the figures. And, unless you are located in an “old” industrial area—such as pre-WWII when 3-phase was required for big motors designed in the 1920’s, you are talking about $1,000 per pole times the number of poles they have to go to pick up 3-phase.

Now do you see why you haven’t got much for a reasonable answer? If there is a better way than there was 20 years ago, please let me know. (I just like to keep up to date, as I’d never mess with 3-phase equipment again if I could avoid it.)

The described machine is set up for industrial power application. Unless you have such readily available, it will, as Pete The Printer, suggests, present much expense in obtaining the required power. And you don’t even want to look at the cost of a 3-phase converter for that sized motor. Although the present motor can be changed out to a single phase motor that, too, will involve considerable expense. Horsepower equals costly motor. And the wiring will also give headache. The safety switches are wired through the motor circuits and unless one is thoroughly familiar with the routing certain disaster will follow any jerry-rigged set-up. I’ve an acquaintence - let’s just call him, ‘Stumpy’ - who switched motors on a power cutter. He now hires people to scratch his nose and perform other necessary functions for him. That’s a great cutter, but it will end up slicing deep into your wallet long before you’ve trimmed the first ream. If the cutter was delivered, and free, you might look at converting it to manual operation. But that, too would involve much twisting of metal and welding of shaft; again at high cost. As tempting it might be, I’d pass on the acquisition. In my opinion

I worked in a shop (25+ years ago) where the owner bought a used heavy-duty cutter and decided to go the phase converter route. What a nightmare! We’d cut for a few days and then for no reason the cutter would just quit right in mid cut. The service man would come out, scratch his head, and eventually we could cut paper again. The owner finally told the equipment company to just take the darn thing back. Never figured out the problem.