Who here knows VFD's

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Have a new lathe coming, and want to get a super simple VFD set up on it. https://www.precisionmatthews.com/shop/pm-tlseries-ultra-precision-lathes/

240v 1ph input
Motor TEFC type, 1725 rpm, 5HP
220 Vac, 60HZ, 3 Phase, 30 Amp Circuit

I need to be able to set it up with the normal power on, motor start and Fwd/Rev
Braking at 1s on low & medium range (gearbox speeds)
Low range, rpm 36, 50, 70, 105
Mid range 130, 180, 250, 380
and 3s on High range - 620, 900, 1200, 1800

Secondary brake switch off the foot pedal.

There are some individuals that I have come across on other forums, but they look to have gone a bit overboard with setting up features, and are using a 3ph input with a rotary phase converter, or have 3ph available, and are building external braking resistors.

The VFDs that I have guessed at (10hp, 30a, 1ph input. 3ph output, internal braking… based on min 30% more than the motor) on the face look like they will do what I want, but, again, I am in the dark as to how to even spec one out, and how to set up. All the different parameters with no layman’s terms as to what it does or for my application.

2

I dont think that phrase even exists anymore

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3

I use Hitachi WJ200 - 22 SF units. My lathe and Milling (Bridgeport) run 3 HP motors. They are easy to set up. You will need a 2.2 kw version.
I don’t use braking at all on either machine. I opted for the remote touchpad on both. I can go from 20 rpms to 1750 on both. Just turn the dial to the speed you want.
Drives warehouse has them in stock. Suppose you have any problems setting it up. The tech support will walk you through it line for line.

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I opted to put it inside a NEMA enclosure like this.
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This one came on the lathe when it had a 2 HP motor. I upgraded to a 3hp motor and unit.
It will eat metal. I can take almost a 1/4-inch pass on aluminum. Just stand back and get out of the way of the ribbon of hot aluminum coming off. You would need a WJ200-37 version for a 5 HP motor.

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Have you called PM Mathews and asked for input on what VFD, and settings will work on lathe? I am sure they will be able to help you. Lots of YouTube videos of VFD on lathes as well that cover settings.

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5

If you plan on running this thing for hours and hours, a VFD drive motor would be a great choice. They have fans connected to the end of the motor to keep it cool with that being said. I have run my lathe and Milling Bridgeport for an hour or so without any problems. My other Bridgeport uses an American Rotary phase converter. They are both the same price, give or take. But the converter won’t control speed.

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One more note. I opted to buy the brand name Hitachi units. There are Chinese copies that are very reasonable in price. As for the track record of this, I don’t know. $400, to me, is worth not having to mess with it again. I get it, though.

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A Lot of reading shows people using the Hitachi, but the 1ph input stops at 4hp. Then I have to go to the 3ph in and a phase converter…$$$

Other VFDs that I have looked at go up to 10hp on 1ph input, ATO GK3000-2S0055G, DURApulse GS23-2020. But I have not found anyone that has posted anywhere using other brands.

So what is the better option?

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Is your motor single phase? You won’t be able to control a single-phase motor’s speed reliably.
Hitachi WJ200- 37 3.7 kw is for a 5 HP three-phase motor. $400. Single 240 in 3 phase 240 out. I take it back you are correct the 37 unit is 3 phase in.

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The American Rotary phase converter is $500 or so. That, with a drive, would be expensive.
Is the Lathe 5hp? That’s a big motor, or is it a big lathe?

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10

Yeah.

The numbers I posted in the OP is right off the specs on the website/manual

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That is a beauty. I believe that you will like it. They make great stuff. Taiwan has a old school work ethic. Many times they are confused and think it’s China. Well, not yet anyway.

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I’m conversing with another guy that has the same lathe, and has done the VFD. He is using the Hitachi WJ200-075LF with 1ph input, but the line card and specs on the VFD show it as 3ph. Trying to figure out where the discrepancy is.

That model is now $751, which is in line with the other two brands I posted earlier.

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Call the Drive warehouse tomorrow. Those people will answer your questions. They are super helpful. If Hitachi makes it they will know.
1-888-476-5944.

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One thing I forgot to tell you. The phase converter is deafening loud. It will drive you nuts if you choose to put it in your work area. If I did it again I would mount it in a back room or even outside in a enclosure. At least 70 - 80 decibels.

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15

I’ve run both name brand and chinese VFDs for several years. The chinese are still holding up fine. For 5hp you’ll need a 7.5hp output single phase input VFD. For braking, external resistors will be your best bet, anything built-in isn’t going to have enough heat dissipation. I like to conceal the VFD and do remote start/stop, fwd/rev & variable speed. I’ve got a 1960’s Monarch 10EE that looks factory (aside from the DRO)

Another advantage of the VFD over a rotary phase converter is that the VFD will shut down if you overload the motor. I burned out a bridgeport motor with a rotary phase converter one very cold morning.

I can’t recommend a static phase converter, you lose 1/3 of your potential hp.

I’ve used factorymation for a supplier with good success, tho for small 1-2 hp VFDs I just use whatever is cheap on amazon.

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Monarch 10EE. WOW, it is arguably the best lathe ever made. 50-year-old versions are still 15k plus.

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I picked mine up 12 years ago and love it, fantastic machine. Maybe not quite the original variable DC drive, but the VFD runs it fine & I enjoy using it every time I have the opportunity.

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Thank you @Bigdaddy2166 and @jdr2710. That Hitachi model that is only shown as a 3ph input does have 1ph provisions, just not in the line card.

Thank you for the heads up on the external braking resistor. I was hoping that the new models had enough built in. Look like I will be adding one of those to the list.

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On this note, the westinghouse VFD’s are also very nice, but you’re going to shell out for them.

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