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wbleeker
05-26-2010, 02:15 PM
I have a Bridgeort clone, a Hartford it runs on 415 volt three phase, what do I need to buy in the way of a VFD?
Will

SGW
05-26-2010, 04:08 PM
Australia's standard voltage is 220 single phase, isn't it?

I'd guess what you need first is either a 220-415 step-up three phase transformer or a new 220V motor.

You might conceivably find a VFD that will do the 220-415 conversion as well as single- to three-phase conversion, but I've never seen one (not that I have a whole lot of experience with VFDs). Maybe somebody else knows.

Alistair Hosie
05-26-2010, 04:55 PM
most of the small wall mounted invertors with full speed control sold here in the uk are 220 volts single phase standard household supply in and 220volts converte3d to run 440 volts machinery out its not 440 volts conversion it runs 440 volt machinery superbly with certain provisos no magnetic on off switches etc and no variable speed machines designed with expanding contracting pulley system at least mine wouldn't work they are great make sure you get one big enough for the horse power you need I always get a bit bigger myself say and extra horse power or so so that it's not labouring at full thrust all the time that's just my humble opinion as his lordship sir John he's very clever on these things and was a great help to me .Alistair ps also ask the suppliers of the vfd's the one I dealt with was fantastic to explain things to me.Oh forgot to say the motor on your machine must be dual voltage to use this system.

MaxHeadRoom
05-26-2010, 05:39 PM
I have a Bridgeort clone, a Hartford it runs on 415 volt three phase, what do I need to buy in the way of a VFD?
Will
Check to see if the spindle motor is dual voltage, that would enable you to use a 220v 1 phase in 220 3 ph out VFD.
The controller and drives are most likely 220 or 120vac 1 ph so this would be less of a problem to switch over.
Max.

EVguru
05-26-2010, 07:22 PM
In the UK most inverters output the same voltage as the supply, although some inverters are being sold with their input stage reconfigured as a voltage doubler to run 415v motors from 240v.

Check to see if your motor can be run in both Star (415v) and Delta (240v). If not, then it's often possible to rewire the motor as I've done on my Lathe and Surface grinder;

http://bbs.homeshopmachinist.net/showthread.php?t=39602&highlight=motor+rewire

My lathe is running one of these VFDs (ebay item 220406176592)
http://i.ebayimg.com/14/!BRgyoNw!Wk~$(KGrHgoH-DIEjlLlvv6nBJ-,ph6,6g~~_12.JPG

And I have to say I'm pretty pleased with the performance so far.

Ryobiguy
05-26-2010, 07:58 PM
it runs on 415 volt three phase

What do you mean by the above? Do you mean "It Runs" as in, it is currently running, to be both a) wired to run on 415v and b) you have it hooked up to a 415v 3 phase supply?

Since you didn't include anything about your power supply, it must mean that it is the same since it didn't need to be specified in your question - I (probably incorrectly) guess that you want to add a VFD for the main reason of adding speed control.

In the unlikely event that this is the case, then I see this on Ebay right now for $40: Automation Direct VFD AC Micro Drive GS2-41P0 1HP 460V

I don't know if 1HP is under-rated because that wasn't mentioned either.

-Matt

J Tiers
05-26-2010, 11:40 PM
220 single phase would be split off 380V 3 phase, .... those two go together (UK 240/415).

A 415 "wye" motor would be 240 3 phase delta at the low voltage setting, which the VFD should make.

We deal with Invertek, out of Wales, and they have single phase input VFDs, such as the ODE-2-22150-1K042, which is 1.5 kW, enough for the usual motor on that type unit, I'd think.

Input 220-240 1 phase. Output 240V nominal 3 phase @ 7 A, about 2 HP.

wbleeker
05-27-2010, 04:26 AM
Sorry I meant the machine is currently hooked up to a 3 phase 415 volt supply, the motor is 2hp, and yes I really only need the speed control, but the soft start and braking woud be good too. Thanks for the replies.
Will

John Stevenson
05-27-2010, 04:33 AM
Will,
You need a standard single phase inverter like EVguru has shown.
240 volt single phase in and 240 three phase out.

You then need to swap the wiring over on the motor from star to delta,
in other words from this:-

http://www.stevenson-engineers.co.uk/files/440v%20wiring.jpg


To this :-

http://www.stevenson-engineers.co.uk/files/240v%20wiring.jpg

If you don't have a 6 wire motor as shown but only three wires as a lot of older motors do then you need to take it to a rewind or motor specialist and get them the pull the start point out and add another three wires.

.

EVguru
05-27-2010, 05:30 AM
Sorry I meant the machine is currently hooked up to a 3 phase 415 volt supply, the motor is 2hp, and yes I really only need the speed control, but the soft start and braking woud be good too. Thanks for the replies.
Will

That's just about the simplest conversion there is. Three phase 415v input fixed 50/60Hz and three phase 415v output variable frequency.

You should be able to pick up a used or NOS older technology drive for next to nothing as they don't have much use in the hobby market. There's no real dissadvantage to a larger drive than you need (within reason) as they can be programmed to match your motor and provide the appropriate protection.

Make sure you can get/download a manual for the parameter setup and control wiring details.