575V RF-30 (Ontario, ends soon!)

[trlvn]

So I was idly scanning an auction site and came across this:

https://hibid.com/lot/81926565/machinist-milling-machine

Amongst the tonnes of crappy pictures, it does show clearly that the motor is 575 volts, 3 phase. The current bid price (with about 11 hours to go) is $275. The machine looks like it's been 'rode hard and put away wet'. Rust on the table, missing handles, etc. Also zero tooling or work-holding, no DRO or power feed.

Just for curiosity, are there VFD solutions that would step up 220V 1PH to 575V 3PH? If so, are they a lot more expensive?

Craig

 

[Hacker]

Really poor picture doesn't look too bad. Handles are fairly easy to make. VFDs don't increase the voltage. You would need a to step the voltage up with a transformer then connect a VFD. I would think it would be easier to change out the motor on that style of machine then start going with three phase unless you are going to be buying more equipment with three phase.

 

[Chipper5783]

I don't believe there is a single device that will take in 240v single phase and output 575v 3 phase. It is quite straight forward to simply take you 3 phase power, however you get it, and then step it up with a 3 phase transformer. I have been running 3 phase 575v machines for several years with a single phase 240v residential starting source. Initially I had a 5hp RPC feeding the transformer, the 3hp 575v motors seemed to struggle. I have since upgraded to a 20hp Phase Perfect to first get the 240v three phase and I am getting better performance.

 

[Chipper5783]

I agree with Hacker that you probably could do the step up and phase convention in the other order. In my case I already had other 3 phase machines (240v machines) - so I need both a 240v and 575v three phase systems.

 

[Hacker]

That is pretty much how my system is configured, with a 15HP idler at 240V and a three phase transformer that steps it up to 440V. I also use a 3/4 hp 440V motor to stabilize the voltage on the transformer.

 

[trlvn]

I don't believe there is a single device that will take in 240v single phase and output 575v 3 phase. It is quite straight forward to simply take you 3 phase power, however you get it, and then step it up with a 3 phase transformer. ...

I should have been more clear. I believe one can buy a box that incorporates a VFD and transformer to go from 110V 1PH to 220v 3PH. It sounds like a packaged solution to go from 220V 1PH to 575V 3PH is either rare or non-existent?

Regarding a step-up 3 phase transformer (220V 3PH to 575 3PH), what sort of cost are we talking about? $250? $1,000? I was curious if there was a cost-effective way to use the existing 575V 3PH motor.

If I were the one buying this particular machine (I'm not), I expect I'd likely buy an new VFD and 3PH motor package to get variable spindle RPM.

Since I'm babbling about 3 phase, am I right that 480V 3PH is pretty much the industrial standard in the USA whereas Canada is largely 575V 3PH? If so, why the difference?

Craig

 

[Johnwa]

A regular home Vfd input voltage is 220. This is then switched between the phases so no step up is required. I think a motor replacement would be the best option.

 

[Tom Kitta]

Motor replacement to 1ph - I am sure you can get used replacement for around $100 - it is standard size. Machine is worth about $1000 as is in Ontario. Current price is a steal.

 

[YYCHM]

And done..... $625 cad. 64 bids.

 

[trlvn]

And closed..... $625 cad. 64 bids.

Plus 13% buyers premium plus HST.

Craig

 

[Tom Kitta]

Very good deal. Less then 800 CAD. Only in ON you can get stuff this cheap.

 

[Chipper5783]

I got my 240-575 3 phase, 6.5kva X-mer used from a rental shop - $100. I think that was a pretty good deal. I have seen good used small X-mers, pretty common under $500 (the used machinery dealers have them because they are commonly needed for powering machines).

 

[Hacker]

I should have been more clear. I believe one can buy a box that incorporates a VFD and transformer to go from 110V 1PH to 220v 3PH. It sounds like a packaged solution to go from 220V 1PH to 575V 3PH is either rare or non-existent?

Regarding a step-up 3 phase transformer (220V 3PH to 575 3PH), what sort of cost are we talking about? $250? $1,000? I was curious if there was a cost-effective way to use the existing 575V 3PH motor.

If I were the one buying this particular machine (I'm not), I expect I'd likely buy an new VFD and 3PH motor package to get variable spindle RPM.

Since I'm babbling about 3 phase, am I right that 480V 3PH is pretty much the industrial standard in the USA whereas Canada is largely 575V 3PH? If so, why the difference?

Craig

Question 1 It can be done with a single phase txer to go from 120V to 347V but you don't see them on the used market very often. So sourcing one could be difficult, maybe I'm not looking in the right places. If you were buying new it would not be a problem. Same for a VFD.
Question 2 If you are patient and a bit lucky you can find a 15/30kVA 240V to 600 3ph for a couple of hundred dollars. The same for a 10/15 hp 240 3 ph motor.
Question 3 600V/575V is more common in Canada then the US but I suspect it has more to do with the power company standards then anything else. There are a lot more small utilities in the US and I suspect that most smaller ones don't want to carry another set of spare transformers in their inventory to accommodate 600V services so they don't offer it.
575/600 in a large industrial setting is a better voltage it saves money on wiring and plant.