James
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| posted on 13/7/04 at 09:35 AM |
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Liam,
Purely out of curiosity, how much does 3 phase cost to put in?
My father told me it was expensive when I was considering a 3 phase lathe I was offered cheaply (and wanted to put in his garage!  ) but I'd
like to know.
Thanks,
James
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Bob C
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| posted on 13/7/04 at 10:58 AM |
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Buy an inverter (RS and Farnell do 'em). You get to plug into a domestic plug and run a 3 phase motor at variable speed.
Most small 3 phase motors are wired star to the mains and if wired delta to the inverter outputs will give full torque/power.
I design these things for a living. When I bought my lathe the seller said he "had to let it go as he didn't have 3 phase"
"Oh dear" I said, trying to keep my face straight... mind you, I get 'em free...
Bob C
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Bob C
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| posted on 13/7/04 at 11:13 AM |
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Just checked what they're going for in Farnell - 1 horse about £180 - then add VAT. Interesting 'cos I know what we make 'em for -
divide by about 4 to 5!!!!!!
Bob C
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spunky
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| posted on 13/7/04 at 11:35 AM |
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Hmmmm. Had a look at RS Comp. There are loads.
Which type would be best suited for domestic application, so I could accidently order the wrong one at work....
John
The reckless man may not live as long......
But the cautious man does not live at all.....
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Bob C
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| posted on 13/7/04 at 11:49 AM |
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To do the job you want a 240V single phase input type.
To keep all the telly's on your street working (!) you want a "filtered" sort with a built in or matched mains input filter.
Then it's how do you want to control it - I suspect you'd want an on/off switch and a pot for the speed. Often you have to pay extra for
"programming" or "parameter" modules,keep it all simple & you hopefully shouldn't need these.
cheers
Bob
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Chris_R
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| posted on 13/7/04 at 12:39 PM |
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Are inverters DIYable? If so how do they go together?
A bit of slapstick never hurt anyone.
http://www.chris.renney.dsl.pipex.com/
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Bob C
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| posted on 13/7/04 at 12:57 PM |
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DIY - only if you're me . . . ;^0
There are evaluation kit type things from people like microchip who are trying to sell controllers for 'em - but they cost more than a
commercial inverter. IGBT and gate drive suppliers also make demo type things, none really a DIY inverter. Your problem is that man years of
development go into making a commercially viable product. Any less & warranty claims kill you off.
These are seriously handy things for the home workshop - if you can acquire one by any means you can probably run all your machines individually by
plugging them in one at a time.
Bob C
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liam.mccaffrey
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| posted on 13/7/04 at 10:04 PM |
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3 phase
james
regarding cost of installing 3 phase
I don't honestly know, we have outbuildings which we used to rent out as business premises but that has long gone now and they are flats now.
but the last person who had the place as a business had a laundry and had 3 phase put for his business. it is still live so i will make the most of
it. I had heard it was really expensive
Build Blog
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drmike54
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| posted on 14/7/04 at 03:33 AM |
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Phase Inverter
Here is how to generate those extra phases if you truly need 3 phase power.
Home Made Phase Converter
[Edited on 14/7/04 by drmike54]
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Chris_R
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| posted on 14/7/04 at 07:53 PM |
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bit complicated then?
A bit of slapstick never hurt anyone.
http://www.chris.renney.dsl.pipex.com/
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Peteff
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| posted on 14/7/04 at 11:30 PM |
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Is this near you James?
http://www.isomatic.co.uk/3phConverter.htm
Looks like a solution but I don't see a price list.
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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kiwirex
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| posted on 15/7/04 at 10:44 PM |
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3 phase...
Speaking from a tremendous ignorance...
Don't car alternaters put out 3 phase?
(after reading the link on the DIY tig welder).
Um...
Can you add them together like you can batteries??
In order to get enough grunt that is.
Picture the locost engine hooked up to half a doesn't alternators ... generating electricity to power the lathe that's building the bit to
hold the engine in...
Maybe not.
- Greg H
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