Single to three phase power conversion to home garage ?

They are easy to make. They also give you bragging rights if you make your own. Some Guy on Ebay sells a little book on how to do it for a few dollars or you can get it from Lindsay books. A small point, but I would just wire the garage for 220 single phase(or the Austrailian equivalent) and the do the phase conversion in the garage. As many others will tell you, used 3 phase motors are cheap and available. You can round up the capacitors and other things easily if you look around. Here is the USA I can buy 5 hp 3 phase motors for $10 to $20 (or less). I might spend $40 on capacitors and another $20 or so on a relay, a box and some wire.

Pete Stanaitis

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Tom wrote:

Schematics for phase converters are available for free

Yes, you are fully right.

Proly the single hottest topic on rcm, no? :)

What's the relay used for? starting the motor, or perhaps switching the caps in/out?

Yeah, def'ly do the conversion after the main 220 panel in the garage. Then, you can get ancillary 3 ph panels to your equipment.

Or, what I did to some extra 220 single phase panels, put another busbar somewhere in the panel for the third leg. Now, altho this leg is not protected, strictly speaking, the other two legs will be, which proly should be sufficient.

Iffin you want to dot yer i's and cross yer electrical t's, then you can get single pole "feed thru" (I think) breakers, which have screw terminals on both sides, that you can wire in to the third leg of yer equipment.

Or, if all you have is those two pieces, just get triple pole feed-thru breakers for each machine, or a 3 p. fuse block, which might already be on the machine.

I think it would be legit to use single phase panels for three phase distro if you used as a corner grounded delta system.

Pete C.

Can one get a corner grounded delta system with a RPC? I am not sure of that. The two legs of 3 phase that come from utility, cannot be grounded. The third leg could not be grounded, either, or else it would not be 3 phase.

Isolation transformer.

Pete C.

OK, you got a lot of good advice from people based in the USA. However, they have a wierd power system, much less power available as a rule than we do to normal dwellings.

My first suggestion is to get 3 phase power supplied. If it's available on the street, shouldn't be a drama getting it. Never has been for me and I've done this 3 times now. This is your single best solution.

Second suggestion is to buy a 240V 1 ph to 415V 3 ph converter from one of the companies that sell them. Friend of mine in Sydney has done this for his country place where 3 ph wasn't possible short of spending $40K and he's happy with the result. Email me (the hotmail addy works) and I'll give you his phone number.

Third, consider buying a couple of 240V in - 415V out (or 240V 3 ph out) variable freq drives. Another friend of mine did this and he's wrapt. Melbourne Machinery has the VFD's. Might need to reconfig the 3 ph motors fromm star to delta or vice versa, I never remember. Usually simple, my B/port 3 ph motors it's just a matter of swapping bus bars over to a different config and the diagram is inside the motor plate.

Fourth, build your own. Option for someone with a lot more time than money. Personally I couldn't be bothered if I had any other choice. I've always put 3 ph power on and forgot about it forevermore.

PDW

I'm looking at connecting my garage with three phase power, but using a single to three phase converter. I will be running a mill and lathe with a total of 4 KW. In Australia there are two companies which sell power converts.

Would someone like to report first hand experience with these single to three phase converts ?

Thanks in advance Tom

Here, that is correct, because our 220V is center tap grounded.

I believe that Oz, like the UK, uses only a 220 (or 240) volt feed to residences, with one side of that grounded, so a corner grounded delta should not only be possible, but actually difficult to avoid. :-)

Enjoy, DoN.