VFD basics for shaping wheel motor

[Rbraniganpipes]

Let me start out by saying I have ZERO electrical experience, so these questions may seem like common sense things to most of you.

Can you add a VFD to any motor? I currently have a dryer motor that I have set up for my shaping wheels and buffing. I believe it is 1/2 hp and know it is 1725-1750 rpm. I would like to have the option of slowing the speed down to do finer detailed shaping. I have been using this setup for a while, as I wasn’t able to afford purchasing a new motor and the VFD controller. I am at the point where I can afford to do that, but also figured it would be worth figuring out if I could attach the VFD to the current motor that I have.

Would it even be worth getting a VFD for that horsepower of a motor?

If not, can you suggest both a motor and VFD that you have used in your shop that would be a good upgrade to what I currently have?

Attached are some photos of my current setup.

[sandahlpipe]

1. VFDs only work with 3 phase motors. You need a VFD to match the HP rating of your motor. Wiring them up isn’t hard. If it spins backwards, you just switch wires 1 and 3 and you’re good to go. Automation Direct is a great place to buy quality product.
2. You can’t vary the frequency of a normal A/C motor. At least not without advanced motors skills involving redoing the windings.
3. An alternative for a budget is a treadmill motor. They run on DC instead of AC. You can find them free or cheap in working order. The motor can be wired up with a potentiometer and a speed controller. I salvaged one and was able to use the circuit boards on the unit itself and spent a couple bucks in a potentiometer. It won’t mount like an AC motor, so you’d have to get creative on that, but they’re usually 1.5-3HP so it’s a good strong motor.

[wdteipen]

Has to be 3-phase like Jeremiah says. You can pick up 3-phase motors cheap because there's not as big a market for them. The VFD converts single phase to 3 phase for you. Most VFD's have a reverse function so don't even worry about whether the wiring is backwards or not. I picked up a 1 HP 3 phase Baldor motor on e-bay for about $40 shipped and a VFD for about the same.

[W.Pastuch]

Why are you guys saying it has to be 3 phase? You can find 1 phase vfds as well, they're quite a bit cheaper than 3 phase and easier to wire.

[sandahlpipe]

At least when you’re working with 110V, I’m not sure you can get a VFD to work with a motor. There are some motors that will work with a router speed controller, but not all, and they usually cause issues with longevity.

I second the suggestion of getting a used 3 phase motor. They’re cheap and plentiful. You can probably find them on Craigslist for $10-$25 depending on HP rating. I got a 10HP for $100. That’s way too much for pipes, but planning a drum sander build with it.

[Sasquatch]

Why are you guys saying it has to be 3 phase? You can find 1 phase vfds as well, they're quite a bit cheaper than 3 phase and easier to wire.

Cuz they don't know any better.

[W.Pastuch]

Oh wait, yeah, I forgot you have 110v as one phase in the US! So I'm not sure if there's vfd for that voltage, they do exist for normal one phase which is 230v.

[sandahlpipe]

Yeah. We do have 220, but only for the big stuff usually like ovens and clothes dryers. I just checked again and couldn't find anything for single phase 110 VFD here. You start to find 220 motors here at 1.5-2HP. For 1/4-1HP, the 110 or 3 phase motors are most common. I tried a router speed controller once, but it didn't do anything for my 110 motors. I guess it only works with a specific kind of motor.

[Rbraniganpipes]

Thanks for the advice everyone.

Being that I have no experience in this category, Is there any VFD that you can recommend, or any to stay away from?

There are so many different motors all with different specifications, so with my limited knowledge, it can get overwhelming. I am noticing that there are 1hp 3 phase motors and 2hp 3 phase motors with RPM's of either 1800 or 3600. What RPM would you suggest I go with? Would I have any use for anything over 1800 RPM when it comes to shaping?

As far as HP goes, what would be the benefit of a higher horsepower motor? Would it be that the motor will continue to produce a consistent speed even when the force of shaping is being applied to the shaping wheel/ shaft of the motor?

Are there any brands of motors to stay away from? I don't know what it is about my general area, but Craigslist here doesn't ever seem to offer anything at a good price when it comes to electric motors, lathes, or tools in general.

Is it possible to find something with a 1/2" or 5/8" diameter shaft so that a Beall arbor can be attached? That is what I am running on my current setup, and has worked nicely for quickly changing sanding discs. If not, what would be another option?

[sandahlpipe]

Common motors are 3600RPM and 1700-1800 RPM. You get more torque and a stronger motor for the equivalent HP at 1700-1800RPM. For pipe making, the 1700-1800 range is perfect. You'll probably be happy with a 1/4 to 1/2 HP. Shaping a pipe doesn't take all that much power. Generally, the motors at lower RPM will have larger diameter shafts and the ones at higher RPM will have lower RPM. This is to handle the additional torque needed to get the HP rating out of a slower motor. I have a 1HP motor on my buffer and 2HP on my bandsaw. Both are overkill for pipe work.

For the Beall arbor, you can get an insert, I believe, that adapts it from 5/8" down to 1/2". I just removed the sleeve and put it on my motor. I very rarely change discs, because I have a 36 grit on the VFD (Which isn't necessary) and a regular 110 motor with the 400 grit french wheel. With a VFD, you can have the motor running at a crawl with enough torque to keep it from bogging down. Even with a 1/2 HP and pushing the block into it quite hard.

For brands, doesn't matter much with 3 phase. Baldor is about the best there is, but anything made in the US is great, and don't let old scare you off. Don't be afraid to dicker on the price for used motors. With 3 phase, there isn't much to go wrong inside, which is why they last so long. I would expect to pay no more than $40 for a 1/2 HP, and more likely $20-$25. There isn't a big market for them. A lot of people replace their 3-phase motors with single phase.

I believe it's this VFD that I have: https://www.automationdirect.com/adc/Sh ... )/GS1-10P5

And my motor is something like this: https://www.automationdirect.com/adc/Sh ... -P50-3BD18

[caskwith]

Motor speed tends to be a personal preference thing. Some prefer 1400, some like 3000. Myself, I like a higher speed.
As to HP, it depends on your shaping style. If you push hard and remove material fast you might want a higher HP, if you are gentler you can use less, speed factors in there too. Higher speed means you need less HP.

I can only speak for myself but I use 3000rpm, my motor is 250W, which is 1/3HP. The motor is actually the cheapest bench grinder I can buy (they cost £19.99), I run them far harder than they should be run but I still get about 2-3 years before it starts to wear out and need replacing.
Jame Gilliam does the same thing, I copied him. Before that I was running a 1HP motor, it was power I didn't need and was just wasting electricity.

[oklahoma red]

I have two motors from Automation Direct along with their suggested drives. No problems with either. There are a lot of options in the programming of the drive. Once you figure it out it is simple to do. I'm sure their drive box would work with other brands of motors so long as the drive is matched to brand X's horsepower.
In case you are not sure how it works, the drive takes the 110V coming out of the wall and converts it to 220V, three phase going to the motor.
A couple of the things that can be programmed are how fast the motor gets up to speed and how quickly it stops. You can also make the motor run faster than it's normal top speed tho I don't know why one would want to for this application. Personal choice.

[Rbraniganpipes]

I am looking for motors in my surrounding area, and am not having any luck. I may opt for the Automation Direct motor and VFD. If i go that route, is there anything else that I need to by aside from wiring/plug in order to make the entire setup work? I see on their website that they recommend an AC line reactor. Is that something I'll need to include ?

[oklahoma red]

I am looking for motors in my surrounding area, and am not having any luck. I may opt for the Automation Direct motor and VFD. If i go that route, is there anything else that I need to by aside from wiring/plug in order to make the entire setup work? I see on their website that they recommend an AC line reactor. Is that something I'll need to include ?

As long as the power coming to your house/shop is stable you don't really need it.

[Rbraniganpipes]

I have the motor and the VFD hooked up correctly, but when I go to turn it on, I get an OC fault. We have double checked all of the connections, and everything is correct. Is it something within the programming that we are missing that is preventing the drive from running the motor? We went through the quick reference programming sheet, and set the functions as indicated, but still get the OC fault.

[sandahlpipe]

Consult the manual that came with the VFD. It should have a reference for the error codes and what the likely cause is.

I got an LV code with the last VFD I set up day before yesterday. Looked it up and it said low voltage. Turns out there was a loose connection with one of the wires.

Chances are, the input voltage isn’t correct if it’s giving you an error message off the bat. That, or maybe you put the line (from the wall-L) voltage into the load (T) terminals.

[Rbraniganpipes]

With connecting the 3 phase motor from the VFD to the wires of the motor, do we connect the ground wire from the VFD to the INS wires of the motor? Or would that be why we are having the issue with over current? Should I be leaving the INS wires unconnected to anything coming from the VFD, and grounding the VFD to any available screw on the motor?

[Rbraniganpipes]

Update. We disconnected the wiring from the motor to the VFD. We had the ground wire connected to the INS wires, which was causing the OC issue. We then reconnected our other wires, and were able to get the motor to function correctly. It was running clockwise, so we switched T1 and T3 to make it spin counter clockwise. We then attached the ground wire from the VFD to a screw on the back of the motor body to ground the motor. Everything seems to be working perfectly now. Thank you all for your guidance!

[sandahlpipe]

Most 3 phase motors don't use ground at all. But yeah, you could just connect the motor housing to the ground. When running, two legs act as return voltage at any given time, so a ground isn't as big of a deal. Glad you got it working.

[Bluesytone]

Why are you guys saying it has to be 3 phase? You can find 1 phase vfds as well, they're quite a bit cheaper than 3 phase and easier to wire.

Cuz they don't know any better.

I have a GS1 vfd that takes single phase input and outputs to 3 phase. works like a charm