CNC Mill Transformer
 

From our sponser we recieve a very very nice CNC mill and we have found out that the part they told us is the transformer is actually the battery backup. So we are in need of a transformer that will step up 208 to 440. I do not know what wattage it need to be but if you know anything about CNC mills you can probally figure it is wayy up there.

Re: CNC Mill Transformer
 

Is there a question in there? 208V is usually 3-phase, do you have that avilable where you are putting this? I think you really should just contact the manufacturer and buy the right part, although it will likely be costly, its less costly than fixing the machine if you feed the wrong power.

Re: CNC Mill Transformer
 

first off we wouldn't be feeding the wrong power if we are feeding it the power it says to on it, and why would be be inputing 208V if it needs 440V

Re: CNC Mill Transformer
 

Can you re-state that in a complete sentences using punctuation and correct spelling?

Can you actually ask a question? I still don't understand the point of this thread.

All transformers are not the same. Without the VA rating it's pretty hard to tell. Also, for 3-phase transformers I believe there are several different winding methods and other differences, so you probably want to get the correct one matched to your mill. Have you contacted the manufacturer of the mill to find out how much they want for the correct part?

Re: CNC Mill Transformer
 

I've never heard of a CNC mill having a battery backup. Can you describe this a little more. Is it just for memory to save the programs that are loaded in it?

Re: CNC Mill Transformer
 

Something that is initially mistaken for a transformer cannot possibly be a backup battery for a CNC. The only thing my shop's CNC needs is a small 9V battery to keep the programs loaded. A transformer would be really big. I think it is worth your money to have a professional electrician or mill repairman take a look at it. You dont want to bust your controller or anything, running it on the wrong power. It would cost a LOT more to get a broken stepper motor fixed than just to have a repairman look at it.

Re: CNC Mill Transformer
 

Why don't you ask you're sponsor, they should know everything it needs.

Maybe you could even get their electrician to wire it up for you, if they have one.

Re: CNC Mill Transformer
 

well we did have a professional electrician look at it and it says back-up battery right on it, I never said it was to keep the programs loaded, someone else did, and we donot know what it is for

Re: CNC Mill Transformer
 

There are many variables for different types of machines. It would very use full if you could tell us exactly what make & model this is..and include any other pertinent information to help you out...

Re: CNC Mill Transformer
 

Sparks,
The part of which you are asking can be one of about a thousand different transformers. As stated before, a 208 to 440 is usually a three phase device. The motor is wound for three phase and that is how it turns and has power. In an industrial setting there is usually 208 and 440 outputs available through the main transformer for the building. Now granted, the transformer you seek only feeds one device, but these transformers are usually very large in size as they are intended to feed a 200-400 amp load or in many cases something even larger.
What we need to know is the "plate" rating. There should be a plate on the mill that states input voltage and input current, horespower, single phase or three phase, etc. Most often it is near the power input but can be on the motor itself. I have heard that some devices actually have a transformer inside which must be strapped by an electrician for the correct input voltage. The connections would be behind a plate with electrical warnings. The warnings are there for your protection. Don't attempt any electrical wiring on this device, leave it to a pro.

Re: CNC Mill Transformer
 

Okay everyone is beating around the bush guessing what it could be and giving helpfull advice about CNC machines but its getting a little wound out. Sparksandtabs, What is the model nmber of the CNC and the battery and what information can you give us? (manufacturer, website, anything else)

Re: CNC Mill Transformer
 

Listen and read Al's writing, he is mostly correct, if not all correct. As an electrician I am going to tell you that the transformer you are looking for will be expensive ( a 32volt ( you would need a 232volt) cost around $800, in 1998 each, and there were 3 ( we installed a 3 phase service and the elevator needed to be run at 240 thus the buck-boost transformer) This would probably be much larger than yours would need to be but you get the idea ). Ask at the locating where you are installing this mill and see if they have a supply of 440 3phase, but you will also have to find out if the mill requires a Y type or Delta. Which are the two most common for a three phase setup. IF there is 440 available in the building see about getting it run to the location ( From the main panel room) to the room which the mill will be in. Another option you could do is see about getting a different motor running at 208 ( Which is usually the only item which will run at the 440) and see how much of a difference in cost between these 3 items ( Transformer, wiring to Mill from mains, and new motor). Most likely the new motor and direct wiring will be less than the transformer. If you do get a specific size ( kva or amps) of transformer you need contact the local electrical supplier and they should be able to get you a quote quickly, Just remember to know the type ( Y or delta, etc).

Mike Aalderink

Re: CNC Mill Transformer
 

-The power rating on the mill is 7kVA.

-It would be really stupid to replace the motors on a $105,000 mill just to get away from buying a $1,500 transformer

-Our sponser was the person who told us that the battery back-up was the transformer

-We are installing the mill next to the room with all the power coming into that wing of the building

-We don't like to just waste money, that is why we are buying the transformer, because it would also be kinda pointless to buy a transformer when we have the power right there

I am not trying to be negative when i say this but everything all of you are saying is common senseexcept for the delta/Y connection or whatever it was we do need to check on that.

I have called a couple places already and we are probaly gonna have a custom transformer made

Re: CNC Mill Transformer
 

You will not find a place to make you a custom transformer for the expense you think. A custom device is extremely expensive.
As to Y and Delta, they refer to the way the power is supplied by a transformer from the power company. A "Y" wound motor cannot be wired to a "delta" output transformer. Many installations use the "Y" which is four wires, three power and one neutral. There are stock transformers available that will do the 208/440 transformation in the 10kVA range that would be suitable. Even at that rating a transformer will run over $1000 and might be up to $2000 delivered and installed. Please contact a local electrical contractor who does these types of installations every day. They will give you a quote and other advice as needed. Hook up the wrong way and your $100K mill is nothing but a precision pile of metal.
Now to the discussion of the backup battery, it is possible that the mill runs on DC and that the battery provides power during a power failure that would otherwise damage a job in progress. It is still possible that the mill has taps internal that would allow it to run on several different voltage inputs. An electrician who specializes in this type of installation would be able to help.
Dude, take the advice and get someone who knows, please.

Re: CNC Mill Transformer
 

well we are getting someone who knows, but a custom trans former wont cost that much, like I said it is gonna be 1500$ and probaly $200 to install it

As for the y/delta we don't know which one it is, that is why we didnt order the transformer yet, also we wouldn't be doing this unless we knew what we are doing first, that is why we are getting advice. Your robotics team doesn't build a robot before they know what it has to do, do they?

Re: CNC Mill Transformer
 

To find that out, you need to contact the mill manufacturer.

You still never actually asked a question in this thread, so how do you expect people to give you answers?

Re: CNC Mill Transformer
 

here\/
although it wasn't technically a question people should still be able to figure out that we need help getting a transformer

Re: CNC Mill Transformer
 

Of course we do! Most people here do! Well not the entire robot but ive planned out our entire electrical system and our team is already working on programming and designing a drivetrain. If something unexpected comes up we adapt our ideas to work but at the very least we are getting experience.
thats not a question. All you saying is what you want. What do you want from us? I still have no idea what the model of mill is.

Re: CNC Mill Transformer
 

I don't know what the model of the mill is either, all we need is a transformer the model of the mill is irrelevant

besides my teacher looked up the specs for the mill online and he can't find them, not even at the manufacturer's website, so the model won't help you any

Re: CNC Mill Transformer
 

I wish I had caught this thread sooner I could have been of some assistance.
The mill is a Chiron FZ 08 W built in 1999. It was used on optical devices and when power was cut the spindle would drop 2 microns (I was told). So, a battery backup was installed on the controls to maintain power. The machine has a control voltage of 200 & an operating voltage of 3ph 400v.

We are using this mill at our school where we do not have power over 3PH 208V. The electrician that looked into the wiring was our school electrician. I am working on having a more qualified individual look into the wiring. I will contact our sponsor to see if they can send an electrician over to help us.

All that being said; I finally found the contact information I was looking for. I was looking in the manuals (4 manuals). It was on a card on the inside of the machine behind the panel of electrical specifications. Any help you can give would be appreciated but, I will be looking into it on Monday.

I asked John (sparksandtabs) to look around and see if he could get some help. While his "question" was vague some of the "help" seemed bent on making him feel stupid. I can assure you that just because he doesn't use his spell check or any form of punctuation, he is a very smart individual. Many others were helpful and tried to get a good question out of him. Thank you.

In the future John, proper spelling & punctuation will keep others from thinking you don't know what you are talking about.

Re: CNC Mill Transformer
 

and every team does that with their robot, what I meant is like before the game for 2005 was released if you build a robot to the previous years dimensions, you would have been screwed, and same thing if you made a robot to pick up balls, you would have needed to redesign it to pick up tetras

Re: CNC Mill Transformer
 

For everyone here is the specs http://www.chiron.de/pdf/FZ08W_e.pdf

Re: CNC Mill Transformer
 

If you are worried about 2 microns why are you building FRC robots instead of high precision satellite instruments? Two microns is less than one ten-thousandth of an inch. How would you ever be able to see or measure the spindle dropping by this minuscule amount? Most common CNC milling machines can keep a tolerance of at most around 4 ten-thousandths if they are fairly new, high quality, and properly maintained and operated. So even if the spindle would drop 2 ten-thousandths, there is still nothing to be concerned about. If it were to drop 2 one-thousandths, then I'd look into the problem (well, actually have a service rep look into the problem) because that is a pretty good amount (thickness of a sheet of paper). So, did you mean thousandths instead of microns?

Re: CNC Mill Transformer
 

Yes, this information is helpful, thanks. The information I was really loking for was the wiring diagram. I think I am going to have to contact the manufacturer for that info.
In any case, you can all see the nice chunk of metal I have filling up some space at our school. Until I can get power to it that is all it will be. : )

Re: CNC Mill Transformer
 

If nothing works and you can't find what your looking for i found the companies website http://www.chironamerica.com/

Re: CNC Mill Transformer
 

http://www.chironamerica.com/distrib....html?id=33814

i would give some one there a call on Monday they seem to be your local distributor... they should have wiring diagrams on hand or be able to get them to you.

Re: CNC Mill Transformer
 

I don't think that he cares about 0.002 mm in the slightest, however, it is quite understandable that the original industrial user might. (If, for instance, it was being used to make mounting hardware for a medical laser, those two microns might be of some value to the person who gets to put their eye underneath it.) They, not the team, were the ones who had a battery backup system installed, after all.

By the way, that mill seems to be just right for a FIRST team; nice and compact, very versatile...if only we all had sponsors like yours, or $100 000 (USD) collecting dust.

Re: CNC Mill Transformer
 

$64,000 on ebay.

Re: CNC Mill Transformer
 

I was just trying to let that one go but you nailed it right on the head. I wouldn't exactly call this machine "compact" though.

Re: CNC Mill Transformer
 

Well, I was just going to let that one go but he (Tristan) is totally off. Did you read my entire post? I'm not trying to just set aside the two microns and say "oh, it is nothing, don't worry about it." In some applications, I'm sure that 2 microns is a huge tolerance. What I am saying is that the inherent tolerance in that machine is more than 5 times that large (at least probably .0004 as opposed to two microns which is ~0.00008). If you are making parts with a tolerance of 2 microns, you won't get it on that machine, which is why I have no idea how anyone familiar with common machining would even bring up anything about 2 microns being a problem (requiring the installation of a backup battery).

Re: CNC Mill Transformer
 

I had heard (as apparently we received the exact same machine from the same sponsor here at RIT) that it was actually .001" that it would drop. Either way, I don't think it's particularly important what the amount it drops, simply that it drops somewhat and wasn't really suited to the application that the sponsor attempted to use it for (which is why they decided to donate them).

Matt

Re: CNC Mill Transformer
 

What is this? Sign up with us and get a free CNC? I want this sponsor! (to all of our sponsors reading this note that we love you guys and wouldn't trade you for an warehouse of CNC machines.... honest....)

Re: CNC Mill Transformer
 

Back to the installation of the mill weather or not your electrician brings it up you could check to see the price to get the motors rewound to operate at the 208. Also keep in mind that you would need 3 transformers, one for each of the phases to boost up to the higher voltage, this coming from myself and my dad in the background, whom has worked with industrial controls and is a master electrician by licence with 25+ years of experience. Get an electrician from a local contractor, then you will be sure to get one whom is licensed and insured and no a lineman or maintenance man as most are in factories.

As is often said please consult a qualified professional.

-Mike Aalderink, Electrician of over 6 years.

Re: CNC Mill Transformer
 

I know for a fact that the type of tolerances you're quoting are indeed valid for a VMC in a production-line setting (e.g. 200 pieces/day, loaded by a robot, high-speed material removal, shop floor environment, etc.). However, with the proper measuring apparatus, and the proper machine, and the proper tooling, and the right conditions, significantly better tolerances can be achieved (as in, an order of magnitude, or better). Diamond tooling and laser interferometry, in combination with a very stable machine can produce complex compound surfaces with tolerances of several microns (of which two microns might be a significant enough portion to worry about, if it would cause a higher proportion of rejects).

I'm not saying that this machine can necessarily do this, because I haven't consulted the manufacturer or the previous user for its specifications; I am saying that there exist similar machines which can, and that minus the fantastically expensive custom tooling, fixtures and metrology equipment (e.g. laser interferometer, etc.), it's conceivable that a small, used one like this could be worth $100 000 (USD). (And I say small, because the ways don't have much travel, the workpiece size is rather limited, and it fits in about the same space as a regular manual knee mill. To clarify further, I was being slightly facetious when I called this "just right for a FIRST team"; it's overkill, I know. If only there was a :facetious: smiley....)

Now, if Matt is correct, we might as well forget this side issue....

Re: CNC Mill Transformer
 

Matt,
This is also another number I have heard. In either case, it won't cause us to throw the machine to the curb. Now for the details on my progress today. I have contacted a local distributer and he gave me a number I could call nationally for service. I contacted this individual who told me where to look inside the electrical panel to check the actual transformers to see if we could wire it to 208V. Nope the primary voltage is (380/400/440). So now I have put in a call to our sponsors to see if they have any transformers laying around. Hey it never hurts. Worst case I will contact a few local electrical distributes to see about a quote. I also ha a co-worker contact a local power company he worked for to see if they might have anything we coil use. Nope.
I sure am learning alt from this.

Re: CNC Mill Transformer
 

Rees,
I think you are getting closer to the info needed. If you know for sure that the machine will only input 440 VAC 3phase and it requires about 10kVA input that is sufficient for an electrician to get started looking for a transformer. He will know that a 480 to 208 stepdown transformer can be turned around and used as a step up the other way and the kVA will get him into a family of transformers that will work. Expect a box the size of a small desk and weighing several hundred pounds to be stationed somewhere close by. If the power vault is indeed in the next room, that might be the best place for the transformer. (air cooled models are the best for your application) A custom transformer is not needed, there should be off the shelf devices that will do the job. He will likely do this anyway, but you want to make sure that the wiring is water and oil resistant and well grounded. Congratulations on a fine acquisition.

Re: CNC Mill Transformer
 

I apologize for not stating a question in my first post. I made it during a class in school that rees2001 was teaching and i didn't want to take up too much time so I neglected to reread it, and i i figured that people would be able to figure out what I was talking about.

Now i wish i could have found that PDF for the mill I looked for over an hour and couldn't find anything.

The reason that i called to get a quote on a custom transformer is because rees2001 and i searched all over the internet for one that would be sufficient for our use and couldn't even find one close.

Now that we are closer to get it working we have to learn how to use it which should be a trip.

Re: CNC Mill Transformer
 

For anyone interested here is the up to date progress. Yes I have been working on this for over 1 week now. Our school electrician came by & we opened the electrical panel and looked at the manuals. Between the 2 of us we figured that depending on the wiring we can hook this directly to our 3ph 208V. The transformer built into the machine has a number of different wiring configurations. I called Chiron for the ... who knows how many times & the guy I talked with told me that "yes, depending the wiring configuration we can hook it up to 208 & it will work." I have asked our sponsor to have an electrician more familiar with machine setup come out & verify our hookup before we run the machine. So, thanks to all that helped, because of your help we may be able to save about $1000.

Re: CNC Mill Transformer
 

That is great news, just the kind you want to hear.

Re: CNC Mill Transformer
 

Ive seen enough misinformation in this thread, it makes me almost sick....
First, I worked in a CNC shop this summer, so I actually have hands on experience working with these machines, it isn't just something I read somewhere.

Ok, about the dropping of the spindle when you lose power, after you turn the machine back on, you re-home the slides. So the spindle dropping would not be an issue. However the better machines I worked with didn't even need that. If there is any doubts at all it takes a full 3 seconds to zero the slides :p Especially on a machine that small with a rapid that fast.


As for tolerances, I'm not saying that 2 microns is something that isn't achievable, but for a $100k machine ...no... I would expect to see the machine be able to go down to .0001" but that's it. As for actual working tolerances... unless your building something that is using multiple pressed pins for holding together 2 pieces, you wont even notice .005" difference. as for measuring down that fine... I would like to see equipment to measure down to 2 microns, for larger pieces... we had a small digital height gauge that went down to 5 decimal places, but that small, tip diameter becomes and issue.


oh and,
Trust me, that is compact. Compare that to a horizontal machine, 11 pallate changer, 240 tool changer, 19.6x19.6" travel, 20,000 rpm spindle, up to 1000 ipm feed rate (feed, not rapid). Yes, that is a compact machine.

Oh one thing that I dont know for sure though, I thought the servo motors on the CNC used DC, not AC, and the power input was rectified, and then fed to the servo amps.