New Motor: 1 PH or 3PH with a VFD?

[Allan Speers]

I keep going back & forth on this, and it's starting to make me a little nutty. Please help me decide:

I need a 3 HP motor for my Powermatic 100 planer. It currently has only a basic on-off switch, so if I add a 1PH motor, I'll want to also get a good mag starter. A good starter & remote switch will cost well over $100, even used. (I don't want a cheapo plastic Chinese one.) Combine that with the slightly higher price of a 1-ph motor, and the current low prices of 3HP VFD's (Around $200 for a basic one) and the price comes out pretty close. The 1PH might cost $50 less or so, depending on the start system I use. So, no significant difference there.

My current thoughts:
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3PH:

A 3-PH motor is more robust. Of course, with my hobbyist use this will likely never matter.

The VFD offers vari-speed. This is a minor advantage with a planer. Nice, but not critical.

The VFD offers dynamic braking, but this is not much help on a planer.
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1PH:

A 1PH motor Might be better if/ when I resell the machine. Many buyers might not understand the whole VFD thing.

VFD's can put a lot of noise on the lines, while 1PH motors don't. This is probably not much of a factor, though.

Using a VFD is one more thing to break, so in some ways the 1PH SYSTEM is more dependable, even though the motor itself is not.
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Well, that's all I got. What's your advice?


THX.

[Martin Wasner]

On a planer, the only advantage I'd see to running a VFD would be having soft start. Other than that, I don't see why you would want to slow the motor down, there's nothing to be gained. Cuts per inch is the same no matter the rpm, (though I'm sure somebody has a differing opinion). A brake isn't necessary to me on a planer either, though I know a lot of big planers do have one. They are usually manually actuated through a lever or pedal.

[Ed Aumiller]

With a VFD you could wire it up so it could be unplugged and plug a different machine into the VFD..
That way if other 3 phase machines became available at a good price you would be able to use them with minimal cost..
Often 3 phase tools are a LOT cheaper...

[Allan Speers]

Actually, CPI does change. It's not a 1-1 ratio, but it definitely changes, due to the feed gearing. When you halve the arbor rpm, you MORE than halve the feed-rate.

Still, like I wrote, this is only a minor advantage as the stock CPI is already quite low.

[John Lankers]

If this was mine, I would get a quality 3hp, 1ph motor with magnetic switch.
I don't see the advantage of a vfd on a planer, neither a 3 ph motor on a planer this size and 3 ph would be a tough sell for a hobbyist when the time comes.

[John Lankers]

Actually, CPI does change. It's not a 1-1 ratio, but it definitely changes, due to the feed gearing. When you halve the arbor rpm, you MORE than halve the feed-rate.

Still, like I wrote, this is only a minor advantage as the stock CPI is already quite low.

When you reduce the cutter speed by 50% you would go from cutting to chopping wood, if I'm not mistaken.

[Matt Day]

Just to be clear, the planer has no motor right now right? If so, I'd probably go 1PH simply bc it's easier.

If it has a 3PH motor now, I'd go with a VFD bc they're easy to setup.

If it has a 3PH motor now and you think you get more 3PH equipment, I'd suggest an RPC.

[Allan Speers]

When you reduce the cutter speed by 50% you would go from cutting to chopping wood, if I'm not mistaken.

LOL ! Yeah, the stock speed is already quite slow.

[Allan Speers]

Just to be clear, the planer has no motor right now right? If so, I'd probably go 1PH simply bc it's easier.

If it has a 3PH motor now, I'd go with a VFD bc they're easy to setup.

If it has a 3PH motor now and you think you get more 3PH equipment, I'd suggest an RPC.

I potentially will have 3 machines with 3PH motors, & I thought hard about an RPC, but I like the idea of separate VFD's even though that's more money.

One reason, as stated in my opening post, is that with a VFD you don't need a mag switch, either for re-start protection or thermal overload protection. (Is it the same with a DC controller? I have no idea.)

Also, with a RPC there is some loss of efficiency, and it's just sort of a minor pain to always have to turn it on-off. With basic VFD's now selling for $200 and even less, RPC's are becoming less attractive.

[Allan Speers]

If this was mine, I would get a quality 3hp, 1ph motor with magnetic switch.
I don't see the advantage of a vfd on a planer, neither a 3 ph motor on a planer this size and 3 ph would be a tough sell for a hobbyist when the time comes.

Exactly what I'm thinking, which is really the only thing stopping me from committing to the 3PH idea. In all other ways, unless I'm overlooking something, the 3PH thing seems to make more sense.

[Art Mann]

Actually, CPI does change. It's not a 1-1 ratio, but it definitely changes, due to the feed gearing. When you halve the arbor rpm, you MORE than halve the feed-rate.

Still, like I wrote, this is only a minor advantage as the stock CPI is already quite low.

Please do a little homework before you make any decisions. The feeder and planer will change speeds at the exact same ratio which will keep the cuts per inch constant. I hope you will eventually come to realize that and not waste your money and degrade your planer. I designed transmission controllers for a major automotive manufacturer and I have a fairly complete understanding of how these things work.