3 Phase stuff on a single phase output

[CurtisRider]

I have acquired a lathe, it is 3 phase and I do not have a 3 phase supply. I have seen various convertors online but I'm confused. There seems to be older rotary ones and these newer VFD units which can be had for seemingly low prices but i'm unsure as to the safety of these units as they seem to be supplied from varying quality suppliers/there are fakes on the market.

Has anybody done a conversion like this on here? There is loads of information online but so much conflicts tat it would be nice to hear from somebody who has done it and talks in less complicated language :$ I have also wondered about fitting a single phase motor instead but like the idea of potentially having an E brake and variable speed that a VFD could offer me.

Le motor:

Le lathe:

[forteh]

My dad has a 3ph motor on his miller wired up single phase, works fine but any major torque load on the motor will trip the breaker in the house. The motor is mounted on a swinging cradle with a vee belt drive, you lift the cradle to release tension on the belts, start the motor up and then lower the cradle to retension the belts. Whether that will work with the lathe, I don't know!

edit: I know the general manager of stm gears who was previously the general manager for danfoss bauer and he knows his inverter drives very well, I'll ask his opinion and get back to you

Edited September 15, 2015 by forteh

[CurtisRider]

I've seen about just running one phase, you can spin the chuck and then switch on the motor to get started, but as you said it runs at reduced power-may not be an issue as I won't do much serious stuff with it to start with. That looks like a fine temporary measure but ideally I would like to make full use of the old beasty! Another option is to use another 3 phase motor as a generator effectively but that all seems a bit too much faffing!

That would be great if you could ask Ed, thanks!

[*gentlydoesit]

Why not get a similar sized single phase motor grafted in there until you sort a supply out?http://www.google.co.uk/search?q=heavy+duty+single+phase+motor&prmd=sivn&source=lnms&tbm=isch&sa=X&ved=0CAcQ_AUoAmoVChMI3Y2SqLL5xwIVUTnbCh0vGQt4

Edited September 15, 2015 by *gentlydoesit

[forteh]

Single phasing a 3ph motor greatly reduces your starting torque but generally once up to speed it's ok.

Just spoken to Wayne and he can do you an ip68 KB unit for 180 quid inc. vat or an ip20 mitsubishi unit for 150 inc. vat although he definitely recommends the KB as it is all analogue pots rather than digital variables and is far more robust (not to mention waterproof housing!).

If that's too rich for your likings and you fancy your chances with a cheapy one you just need a 230-415v 600w inverter

[CurtisRider]

I've potentially got a single phase motor sitting at my parents place but ideally I'd like to keep the 3 phase set up for the reasons above (also buying a new single phase motor and starter would cost as much as a VFD anyway!)

That's great Ed, thanks for your help! I'm not looking for the cheapest solution (although the lower the cost the better of course!) so I'd happily pay the extra £30 if its necessary/beneficial. I have also been offered a S/H rotary one for £100 that is suitable, so it seems I have a few options! I'm hoping to get the lathe back to mine this weekend, so once it has been reassembled I shall investigate further, I also need my big ass belt sander to sell so I can actually have room to fit the lathe and that will also pay for the convertor. I know it all works as I used it a few times at work, so that's a start!

[GavLawson]

As said above your best bet is a VSD/VFD just bear in mind you will need a larger supply to suit. You will also have to de-rate the VSD by at least 50% if you supply a 3ph VSD with single phase.