220v siingle phase to 440, 480 or 575 volt 3 phase

I am looking for a Hardinge HLV-H. The ones I have seen all have 3 phase motors with one of the following voltages, 440,480 or 575.

My building has 220 single phase. I am checking to see if 3 phase can be brought in.

Question, in simple terms because I do not know much about electricity - How and what do I need to go from single phase to these 3 phase voltages? Cost?


Thanks
Greg

Figure on at least 2-300 dollars at the low end as you will need a transformer with a vfd or a few capacitors, all bought second hand. You will get more details if you supply more info.
Rob

robvds said:

Figure on at least 2-300 dollars at the low end as you will need a transformer with a vfd or a few capacitors, all bought second hand. You will get more details if you supply more info.
Rob

Click to expand...

Rob,
What other info would be helpful? I will try to provide it.

Mrgt350 said:

I am looking for a Hardinge HLV-H. The ones I have seen all have 3 phase motors with one of the following voltages, 440,480 or 575.

My building has 220 single phase. I am checking to see if 3 phase can be brought in.

Question, in simple terms because I do not know much about electricity - How and what do I need to go from single phase to these 3 phase voltages? Cost?


Thanks
Greg

Click to expand...

I just did this.
I am a rank beginner but can say that for me, once I figured out what to do, the actual doing was quite simple and straight forward.

You might want to read through my thread on the subject as I was trying to sort it all out:

http://www.practicalmachinist.com/v...transformer-jugling-numbers-380v-50hz-257089/

I purchased a single phase used 3KWA transformer for $75 and a Hitachi WJ200 series VFD for $320.

A day to wire it up and the machine is running great.
For my dime, I would go the VFD route for all the perks which come with a modern drive. The cost is a wash over installing a RFC it seems.

This forum was exceptionally helpful.
Both in regards to the direct advise I received and the wealth of information on this subject and others which can be found in the archives.

Read that thread- the posters really spell it out on how to proceed.

Size the components for your load, wire it up and you are good to go.

How many horsepower are you trying to drive?
Are you going to push the machine to this max horsepower.

I have to assume you can wire the motor for 240VAC 3PH. If your not pushing too much over 5HP, you can do this with single phase 240VAC, and use a VFD (generally over 3HP you need to use a larger then needed VFD and derate, ~60-70% of VFD).

I looked at Hardinge HLV-H and looks like a 11"x18" lathe, this should not be more then 3HP, but I'm guessing. My 12"x24" lathe is 1HP, my 18"x40" lathe is 7.5HP.

But if you really need lots of 3PH power, this is a pretty major upgrade to the service. Your local county/city building department (I think this is a state controlled thing in MN, so substitute state for local gov., but I assume a permit is needed), it's getting tough to do electrical work without at least a journeyman's license, and only if the state will inspect this without a Master sign-off. At any rate the monthly meter costs are considerably more for 3PH. And there may be a minimum KW-Hr consumption (you'll pay the minimum at least). But I'm thinking this is more then $3K for starters (assuming you have to hire an electrician).

I would assume if the HP is less then 3HP, the motor would be 240-480VAC, but I know nothing about Hardinge HLV-H. 3PH motors are pretty easy to get off eBay, if voltage was a problem, but then you may need a good drill press or mill to make an adapter plate if you can't find the same NEMA motor frame mount, all depends on how old the machine is. The current standard from my memory goes back to early 60's.

ignator

Also some VFDs designed for 3PH input, require this, and will not operate, so selecting one without this limitation may be important. I'm using a Mitsubishi 10HP VFD on the 7.5HP motor. Their manual will indicate this if you know where to look.

Generally the hardinge lathes I have been looking at have been 1 1/2 hp. Voltage of 440 and 575 on a Canadian machine. Would be nice to get a 220 volt unit. Then I would just need the phase converter.

Most HLV-Hs have two-speed consequent pole motors which are single voltage.

I suppose the very late ones, like their Taiwan clones (Cyclematic, et. al.), may have VFDs.

There is very little demand for second hand 480/600v vfds. This means you can buy them on ebay for very low prices.
Rob

Very true, but you must have mains of that higher voltage. So this puts the problem back at using a transformer with 1:2 ratio or more, then add in a phase converter.
Much cheaper to replace the motor with 3HP or less with single phase. This is ~$200 for new off eBay.
I wish those 480V VFD would have a strap to operate at 240V, the major difference is the power transistor breakdown voltage, it's very easy to have the low voltage power supply for the microprocessor and control electronics to be wide input voltage range, at the very low power level these circuits consume. At least that's my thinking, I've used many VFDs at my personal home shop, I remove the single phase motors off the lathe, drill presses, and bandsaw, and replaced with 3PH motors and VFDs either from eBay or from dealers electric. The Wells Index, rockford miller, all have dedicated VFDs.
I've been lucky they are all 240VAC motors on existing machines, as well new ones I've gotten from Grizzley.

ignator

The phase converter, either static or rotary can cost more then a new VFD. And you don't get variable speed with a 60Hz phase converter. As well the VFD provides motor protection (other then over heating if you run it too slow, but this can be addressed with a temperature switch, that can be connected back to the VFD for shutdown, I've never had a need to addressed this issue). I've also never had a problem with VFDs causing voltage transients that damage old motors. The rockford miller has a very old conversion of what was an overhead drive flat belt machine (~30's age of machine, but pre 60's conversion using 3PH motor). As well the Wells-Index verticle mill has a late 60's motor on it. I think in the early days of inverter 3PH converters, there may have been a problem with transient switching causing insulation breakdown. I've not experience this problem with VFDs of 15yrs and newer designs. But again, I'm not pushing any of my machines to continuous full power output where this transient spikes would be maximum.
ignator

I do this at home. 10hp Phase Perfect to get 3 phase, transformer to get 575 volt. Not cheap but works very well, runs all my machines at the same time if needed.
Bob

Is your input power 240VAC or 575VAC? I looked at their web site, I did not see where they would boost voltage to a high volt 3PH, but I did not look at their details, they do show a block diagram of their system, looks like they reuse the L1 and L2, then use a switching power supply to create L3. but my confusion is that L1 and L2 are 180 degrees phase, and adding the 3rd one would be 90 degrees from these. I know I'm missing something, as in the pdf they show 120degree phase diagrams. But I don't intuitively understand this. Darn.
ignator

So it sounds like I need a phase converter to get single phase up to 3 phase. I assume that I need a rotary style phase converter. Then a transformer to get from 220v 3 phase to 575 3 phase.

Can you point me to some specific transformers that will do this?

Again, I am looking at a lathe that requires 575 volt 3 phase and I currently only have single phase 220.

Thanks
Greg

There are several options to solve your problem. I looked at some 575 volt HLV-Hs a few years ago and faced the same situation you have then I bought a Monarch 10EE and got it a lot deeper.

Here is an idea not yet presented: With a VFD, you can get the motor to operate from the high speed windings and not use the low speed ones. The VFD will take care of the variable speed and the torque will be the same. Now this opens another possible solution:
Replace the 575 volt 3 phase motor with a 230/460 volt single speed motor with the same rpm as the high speed on the orginal and use a 240 volt VFD to drive it. This is more work but will provide a good working solution and you do not have to deal with 575 volts. just make sure the replacement motor has the same frame number as the orginal and it will bolt up just fine. It will be necessary to rewire the lathe controls so they control the VFD. I do not have a Hardinge wiring diagram and can not tell you exactly how to do it without one..

Here is an idea not yet presented: With a VFD, you can get the motor to operate from the high speed windings and not use the low speed ones. The VFD will take care of the variable speed and the torque will be the same. Now this opens another possible solution:
Replace the 575 volt 3 phase motor with a 230/460 volt single speed motor with the same rpm as the high speed on the orginal and use a 240 volt VFD to drive it. This is more work but will provide a good working solution and you do not have to deal with 575 volts. just make sure the replacement motor has the same frame number as the orginal and it will bolt up just fine. It will be necessary to rewire the lathe controls so they control the VFD. I do not have a Hardinge wiring diagram and can not tell you exactly how to do it without one..

Click to expand...

Perfectly sound advice but...

The HLV-H motor is a large frame (because of the double windings) and it is balanced to 0.0003" p-p, so an exact low voltage replacement will be expensive.

The motor's two speeds are a 3:1 ratio (4pole/12pole ?) so unless you use an expensive sensor-less vector control drive the low speed torque may well be lower than expected. - I have tried this (slowing the hi-speed) on my own VFD driven HLV-H; for many uses i.e. small diameters it would be perfectly OK but I doubt it would have turned a 6" bar that the full torque low-speed handled.

FYI my diagrams are here: HLV-H VFD conversion

Mrgt350 said:

So it sounds like I need a phase converter to get single phase up to 3 phase. I assume that I need a rotary style phase converter. Then a transformer to get from 220v 3 phase to 575 3 phase.

Can you point me to some specific transformers that will do this?

Again, I am looking at a lathe that requires 575 volt 3 phase and I currently only have single phase 220.



Thanks
Greg

Click to expand...

Greg, most of my machines are 600v. You need a transformer and a phase converter. You can step up the voltage first (my preference) or you can convert to three phase first. Keep an eye out for a 3kva transformer, check used electrical suppliers and demolition yards near you so you don't have to pay shipping.I do not like to run a transformer on the output of a vfd, so if you buy a 3 phase transformer you will probably have to use an RPC.If you step up the voltage first,(single phase), you can buy a vfd cheaply or build an RPC using a lot less capacitance than a 240v model would require. I would not even consider swapping the original motor, it is part of why these lathes are such a joy to use.
Rob

Just found out that the voltage into me building is at 208. The city electrical guy called it 12208. Also found out that the lathe is 550 volt not 575 like I was previously told. Not sure if this really matters just thought I would correct it for the thread.

Most transformers have a few taps to allow you to compensate for just such differences. 550 is the ''old''575, still considered to be 600v class.
As a general rule motors are OK within 10% of labeled voltage. Your 550 motor is of the highest quality and would probably be happy running on 480v.
Rob

Mrg350; you were told you have 208VAC single phase? If it was me I would get a meter and check it. Then check to see if you have 120VAC to Neutral. If you do then you might have 2 legs of a 3 phase power. A little transformer manipulation and you can make 3 phase.
Years ago they would connect 3 phase without charge if it was available on the pole, I'm told they still do is some areas. If they will give you 3 phase get it! Only drawback is they will connect you to a demand meter that will just about double your current bill.

Frank

Good news today. I was told by the power company that I have 3 phase power up to my meter. All I need to do is have an electrician put in a panel. I will be checking on the cost of this. Monthly charge would be about $15. I have also found a couple lathes that are 220v. So now the question would be - Put the 3 phase in and pay the $15 a month or do a phase converter or vfd to get the 3 phase out of the single phase I have now.

Greg