It's ALIVE... (1959 P90 Lathe - Reeves Drive w/VFD)

[MRDucks2]

After going completely through the old 1959 Powermatic P90 lathe mentioned in a previous post, getting 240 volt single phase ran to where I needed it, verifying the motor connections for the proper voltage (the free drive I received is 230V 3 phase output, not 460V) and temporarily setting everything up to test the motor, it WORKS!

Please keep in mind that this is a test run only to verify the motor operation and work through the Reeves Drive at speed by someone with decades of experience in drives and rotating equipment up to 60,000 HP and 38,500 volts. If you have never seen a Reeves Drive work, this will be good for you. The drive will go into an enclosure and the belt area of the lathe has a solid, cast iron cover that bolts over it for normal operation.

Next steps will involve building and mounting the drive enclosure, rewiring the motor leads to the drive (I just do not like the wire used or its condition) and better routing the wiring from the motor to the drive. The Drive is presently set with max and min frequencies. I will measure actual output speed and determine the ideal limits, program the drive and get it ready for the first test turning wood.

Concerns anyone should have for an application like this is both driving the motor too slow, which can result in overheating, and driving the entire machine too fast. This lathe has an original motor, also. While it did not likely see much heavy use (the majority of these were used in schools and at some point in history the old lathes in school become more legally cumbersome and generally sat unused) it still has old wiring, windings and bearings. A replacement will be ordered and on hand. Fortunately, with a decent drive, you can easily control your operating ranges and keep everything safe.

 

[Dalecamino]

Congratulations!

 

[mark james]

I suspect you are having a wonderful time getting it back into the condition you want.

Nice video! Have fun.

 

[leehljp]

Since you first posted the purchase of the lathe and your intentions of use a VFD, I have been looking for a VFD to use on my Grizzly Reeves Drive lathe. The motor on mine is 120, but switching it to 220/240 is fairly simple.

I have a question on something I do not understand: What is the difference between a 240V VFD Single Phase and 240v VFD 3 phase? I am asking in terms of how it will work on a motor such as the 2hp Grizzly set for 220/240? Will the single phase be connected differently than a 3 phase to the 2 hp motor?
I don't know enough about 3 phase vs single phase to know the right way to ask. When I go to read the differences, I get technical mumbo jumbo that doesn't answer my questions to my understanding -i.e. I get technical answers, not practical answers which is what I am looking for. Should I be looking for a 240V single phase output VFD or a 3 phase output for the Grizzly?

OR Is the single phase vs 3 phase referring to the INPUT side to the VFD?

thanks for any help anyone can offer.

OK, in reading more on the VFDs, I am seeing that that output is mostly 3 phase and requires 3 phase motors. CAN or HOW does one change a motor from single phase to 3 phase? My wiring diagram on my Grizzly shows how to change from 120 to 240, but that does not change the phase - in my understanding. Is that correct? SO how does one change the phase of a motor, or can it be changed?

(I used to build tube and transistor SW radios, AM/FM radios, stereo Amps and other electrical things as a kid and young adult, and the mechanics of connecting things together was not a problem. All I did was follow the diagram/schematic. That is what I am trying to get into my mind with this. That is the reason switching the Grizzly motor from 120 to 240 isn't a problem - I have a simple diagram of it. But I can't get my head around the single phase vs 3 phase in hooking it up. I hope there will be a clear diagram.)

 

[MRDucks2]

There is a lot that could be said, most of which you have probably read and did not help. So I'll shoot for the more basic conversation as it applies to our home workshops.

From the perspective of day to day turning in home/hobby workshop you will not likely see a real advantage between a single phase application vs a three phase application.

I would saying the biggest differences that we in the home/hobby shop would notice are:
- 3 phase motors do not require a start capacitor.
- technically a 3 phase motor should have a better power factor and be more energy efficient, but at, for instance, 2 HP it is so negligible to not be real important or less than 1/8 HP of power factor gain.
- a 3 phase motor is easier to reverse the direction of.
- a 3 phase motor is easier to start under load than a single phase motor, but, again, our loads are relatively small.

I cannot speak to the single phase VFD's as they are referred to. Never used one or even seen one. However, I do understand that single phase VFD tend to require derating of the motor HP, due to current limitations, and only a few of 8 or 9 different types of single phase motors will work with one.

Being familiar with 3 phase, I like that a decent drive like the Allen Bradley one shown does a lot in protecting itself and the motor. It can ramp the speed up and down, ensures it does not overload the motor, monitors for motor and supply problems while protecting itself.

In this 2HP range, there is not a big price difference overall for motors, controls, etc.

Hope this helps.

 

[leehljp]

That does clear up a lot. It helps me to know what to look for going forward.

OK, I am learning. Everything I see for VFD is that its output is 3 phase. On checking with my lathe, the older versions without the DRO, it would work, but since they added the DRO around 2014, the motors changed somewhat. I am sure I could get around that but I will just have to take what I have and maybe get a newer model lathe later.

Thanks for your help.

 

[MelaniePayne]

Wow! Nice job, man!

 

[MelaniePayne]

Wow! Nice job, man!

Hey, you're doing great. I want to be able to use similar parts, but the voltage was a little lower? It's just that a friend of mine worked as an engineer for a company and was asked to make a new engine for them. And the problem is that we have the right parts, but the voltage is slightly different, so I think to try to collect or not. Or you can buy any old automatic parts for our business somewhere. It's just that we don't have a lot of money right now, so any details will do, even those that have already been used by different companies. Here I Googled and came across this site automation-usa.com, where I think to buy or not.

 

[MRDucks2]

Automation direct comes highly recommended. I am sure automation USA is fine, also. And good company you will be able to call the up, tell th what you and what you are trying to achieve and they will be able to give you a direction to look. The range of drives from Allen Bradley is huge and their likely something to meet your needs for $300 or less new, about half that on the used market.