[SmoothMove]

Hey fellas. I'm new to cnc, i have a couple smaller manual mills that i have learned on over the last few years, and have finally taken the next step to cnc. I bought a 1991 Tree 325. It has the 3500 spindle with a Dynapath 20 control. I just have a couple quick questions, if anyone would be kind enough to help me with. I have the original manuals(For Dynapath control, and Tree 325), and reciepts for the mill(I bought it from the original owner). It comes wired for 230v, but for some reason they had it wired for 440v. Now i need to buy a phase converter for it, and am not sure what fits the bill. I have the 5 horse spindle, and know i should go with a 10 horse rotary converter, but does voltage play a major roll in this? Also, need to buy a compressor for it, any recomendations for this, as i only need what will be needed to get me by(I don't need air for any other machines in my home shop). Thanks in advance for any help, i'm honored to be a part of the forum. Also, please excuse my inexperience in the subject of cnc, all help is appreciated. -Thanks-

[jalessi]

SmoothMove,

Instead of a primitive rotary converter, why not get a VFD to run the spindle.

Welcome to the Zone,

Jeff...

[SmoothMove]

Thanks for the response my friend. I guess thats a good question, i just don't really know what my options are. Do i only need the 3-Phase for the spindle itself, and everything else can be run from single phase? Again, please excuse my lack of knowledge here.

[jalessi]

SmoothMove,

A VFD converts single phase to three phase to run the spindle motor.

The CNC controls should run off single phase.


Jeff...

[jalessi]

See the attached link for a 5hp drive.

http://www.driveswarehouse.com/Drive...FD/PC1-50.html

[SmoothMove]

Jeff-
Thank you so much for you help here, i just didn't know that this was an option. After reading your original response, i researched the internet a little on the subject. Seems like the right route to go for me as the noise level of the RPC would be an issue, not to mention quite a few people recommend it over the RPC(Sometimes refered to as "Old" tech). So do i just get a VFD rated for 5 horse(I have the 5 horse spindle), or do i need something larger to accomidate it?

[SmoothMove]

Thanks for the link Jeff. See, heres the other issue i have, in the paper work with the original purchase of the machine, they had it changed from the 230v that the machine comes with, to 440v for whatever reason. Now, do i try to find a VFD that can do the 440v, or have it wired back to the original 230v? I know nothing(And i mean nothing) about current and such, so i will most likely have to pay an electrician to come and wire everything after i purchase the VFD.

[jalessi]

SmoothMove,

Changing the machine back to 230v will be a cake walk for someone familiar with your machine.

If you are installing the machine in your home 440v is not a option.

Where are you located?

Jeff...

[SmoothMove]

In CT. Is it possible for me to hire an electrician to just change it back to 230v, and then install the VFD? Is this something that a "Regular" electrician will be able to do you think?

[jalessi]

SmoothMove,

Yes, a capable electrician that can read electrical schematics will.

Jeff...

[SmoothMove]

Jeff-
Thanks so much, i appreciate you taking the time to help me. The info you provided has helped to steer in the proper direction, as opposed to the "Direction" i was headed!! Haha Thanks a bunch my friend, all the best.

[mikej65]

Your spindle motor is almost certainly dual voltage. Going back to 220V is just a matter of reconnecting the leads for low voltage. Generally, a step-down transformer(s) is used to get back to 110V for your controls and drives. These usually have dual taps, so they can be reconfigured to the 220-110 wiring instead of 440-110.

You probably have a VFD currently driving the spindle. This would currently be one with 440/3ph input and 440/3ph output. This would be replaced with one rated for 220/1ph input, 220/3ph output, and 5hp or more. It is also possible in some cases to use a VFD nameplated for 220/3ph input and derate it 33-50% for single phase input, but I won't get into that discussion here. Note that the VFD only runs the spindle. If you have other 3ph motors, like a coolant pump, you will either have to run a them on a small VFD or replace them with single phase units.

There is a fair amount of wiring to the VFD. These connections control spindle speed, direction, start, stop, and relay fault signals to the control. You will have to work off of you current wiring diagram and the VFD documentation to get these correct. The VFD will also have to be programmed for things such as control method and braking time.

Mike

[SmoothMove]

Mikej65-
I don't plan on running any coolant as of now or in the near future. At this point i do all "Dry" milling, maybe down the road i will look into it though as i learn how to run the controls. Besides the coolant, the spindle is the only part that i can think of that requires the 3 phase power. Thanks for that my friend.

[SmoothMove]

So after reading the replies you where kind enough to offer up, i called around some suppliers to see what was needed exactly. Well, they gave a bunch of conflicting answers to say the least. What i was told(By Yaskawa), was that a VFD won't work and wil possibly damage the spindle drive. I am leaning toward a 10hp rotary phase converter. One thing i really liked about the VFD is the noice level, but i guess i will have to live with the noise of the RPC. I'm assuming(And probably wrong here) that the machine "Hooks" up to 3 Phase power and distributes the proper power(1 Phase) to the Servos/computer. If i went with a VFD, i would have to hook everything besides the spindle to single phase separately??? But if i go with a RPC, i just cover all basis with the one 3 Phase hook up???? As said, i'm really inexperienced with this. Thanks for taking pity on me fellas, its appreciated.

[underthetire]

Yes, the computer and drives are single phase on that machine. IF i remember correctly, the servo drives, either MSI or baldor, were 110 VAC in with a 90 VDC output. The control was a single phase input to the power supply, i think those were tapped for 110 as well, but it's been 10years since I had one apart. The coolant pump was just a cheapo single phase unit in most of the J series, and most people never used them and replaced it to an automatic spray mist set up. That leaves the SDU. That was 3 phase 220 for sure. I would really look further in to a single phase input/3phase output replacement, since that drive is NLA and would require a replacement when it goes out. Notice I said when? That was the most common failure after 5 years on those machines. Now all of this is great if you have someone knowledgeable in this stuff. If you can't do it, just go to a rotary, it would be expensive in labor to pay someone to do it.

[jalessi]

SmoothMove,

You are getting half baked answers from whomever you are consulting with.

The VFD would take the place of the existing spindle drive.

Jeff...

[SmoothMove]

Underthetire-
Yeah, i think i am just going with the RPC(10HP). I did talk with Yaskawa about changing the drive to be single phase, but i would have to hire someone to install it. I'll just go with the RPC for now, and deal with the spindle retrofit down the road. The machine seems to be in pretty decent shape as the fella that i bought it from was real "On top of things" with the machine. I have every piece of paper(Original reciepts) ever associated with the purchase and/or manuals(One owner besides me). Not to mention he bought it new for one job, so when that contract was up, the machine just sat in a heated shop. So i'm hoping to get some use out of the spindle before it desides to go into retirement!!! Hahaha -Thanks again-

[SmoothMove]

SmoothMove,

You are getting half baked answers from whomever you are consulting with.

The VFD would take the place of the existing spindle drive.

Jeff...

Oh, i see. That makes total sense now. So i buy a VFD to replace my Yaskawa spindle drive(Single phase VFD, and use my regular house current)??? And yeah, i've talked with a bunch of boneheads over the phone trying to find the "Correct" solution to this. It would be nice to know exactly what other 325 owners are using for this. Thanks again Jeff, you have been helpful.

[jalessi]

SmoothMove,

I have repeatedly explained what other Tree users are doing.

Jeff...

[SmoothMove]

My friend, my intention was not to bother you with the questions. Honestly, reading your post made me think you where pointing out what i should do in your opinion, i didn't see you say thats what other Tree owners where doing? As i said i am new at this stuff, and know nothing of cnc machining. Anyway, i appreciate your help man. -Thanks-