David E. Posted May 18, 2008 Share Posted May 18, 2008 Hi, Here in UK the largest motor on single phase is normally 3 or 3.5 hp, so to run a decent size power hammer I would need a phase converter to give me 3 phase from a single phase supply. Does anyone here use a converter to run a 4kw/5hp or bigger motor from a single phase supply and are you happy with it?? Quote Link to comment Share on other sites More sharing options...
LDW Posted May 18, 2008 Share Posted May 18, 2008 A buddy of mine has a machine shop behind his house and has been running end mills, lathes, and surface grinders for years with no problems. This web page has a similar set-up to how his is set-up. Don't know if it would do any good in the UK though.Building a Three Phase Converter Quote Link to comment Share on other sites More sharing options...
David E. Posted May 22, 2008 Author Share Posted May 22, 2008 Thanks LDW, apparently power hammers put a heavy load on the supply at start up and I just wondered which converters worked and which didn't. david. Quote Link to comment Share on other sites More sharing options...
J W Bennett Posted May 23, 2008 Share Posted May 23, 2008 David, I run 2 converters in my shop, one is a small 1hp and is dedicated to a hydraulic pump. been in service for about 7 years, the other is a 7.5hp that I use to run several pieces of equipment. it has been in service for about 3 years. I built both and have had no problems with either one. in my opinion rotary is the only way to go for shop equipment. I'm not powering any compressors with it but end rush has never been a problem. John Bennett Quote Link to comment Share on other sites More sharing options...
metalmaster1766 Posted May 23, 2008 Share Posted May 23, 2008 i built me a rotary phase converter a few years ago, it is just a 2 hp motor, they work great and are very easy to build, mine cost me about 2 hours worth of time to assemble, that was after collection the capacitors, which i got from old outside central A/C units i plan on building a bigger one someday the thing about a roto phase is, you idle motor, which is in fact the phase converter itself, can run whatever size motor it is - if you get a 5 hp 3 phase motor and turn that into your roto phase (thats what i call them) you can run a 5 hp machine with no problems, now say you have 4 machines all with 3 phase motors, 1 or them is a 10 hp motor, you can run that by turning on the roto phase (5hp) plus starting another 5hp motor and let it just idle, then you should be able to turn on and run a 10 hp motor and run a full power the hp adds up with all the idle motors thats why i need a bigger roto phase, mine is 2hp i have a 7.5 hp cutoff saw, i hafta turn on all the 3 phase machines and let them idle so i can get my saw to work, i onl;y have 1 other 2hp motor and several 1hp motors, so i hafta turn my roto phase on, then the 2hp motor, then 3 other 1hp motors to get the saw to work, it just about max's out my amps by doing this, but it does work you can buy one for several hundred dollars, or build one for cheap, and if you are good and resourceful at collecting things, you could build one for less than $25 maybe even free (like i did) oh yeah, most small motors (like my 2hp) doesnt need a start up capacitor, most (not all) will start to turn just by adding the 2 single phase 120v power to it, then you use the capacitors to even out the 3rd leg of 120v to as close as the others as possible bigger motors need the startup capacitors, or a pony motor and belt to get the bigger motors to start spinning, you can use a pull rope to start it spinning and then turn on the power, then is will start up, ill look for the link i have about them, the guy lives here in Cincinnati, he sells a disc on ebay on how to build them, it is like $2 and he can email a down loadable file or for $5 he will send a C/D he also will help out as best he can thru email if you have problems building one i bought him breakfast (from Mcdonalds) and he gave me a disc, has lots of info on them i would try to send it to you but it has some type of copy write thing that makes it impossible to do Ron Quote Link to comment Share on other sites More sharing options...
arftist Posted May 24, 2008 Share Posted May 24, 2008 When you say decent size, what do you mean ? my 35 kg mechanical hammer runs very,very well on 2hp. Quote Link to comment Share on other sites More sharing options...
stevet Posted May 26, 2008 Share Posted May 26, 2008 I have a static converter that i got second hand , think its 11kw, i regularly run a 8hp motor with it, Steve Quote Link to comment Share on other sites More sharing options...
steveh Posted May 28, 2008 Share Posted May 28, 2008 i went and spoke with the outfit that built my phase converter on pricing other ones.they dont make them anymore,too old school.,they now have frequency drives.they are programmable and are cheaper than the converters,very cool little units. Quote Link to comment Share on other sites More sharing options...
Chris Pook Posted May 29, 2008 Share Posted May 29, 2008 I run my Nazel 3b which has a an oldschool 10hp motor with a phase converter. No issues with it. Just make sure you have a good single phase power source. Quote Link to comment Share on other sites More sharing options...
David E. Posted May 30, 2008 Author Share Posted May 30, 2008 (edited) Thank you all for your replies and experiences, I am now much more informed as to how I should proceed. I have a dedicated 240 volt single phase and I also have what is called here "split phase" or 2 phase it is still single phase but 2x 240 volts making 480 volts. I only use this for my 300amp stick welder. I want to power a Sahinler with a 4kw motor (5.5 hp) 3 phase. I have noticed that you commonly have 5hp motors on single phase in US where the largest we usually can get here in single phase is 3hp 240volt. I had not considered making my own, (electrics are the devils work to me:) ) but I shall look again. Thanks again. David BTW Chris what is the size of your converter to run the 10hp and is it a rotary? Edited May 30, 2008 by David E. Quote Link to comment Share on other sites More sharing options...
Chris Pook Posted May 31, 2008 Share Posted May 31, 2008 Yes its a RotoPhase. I bought mine used its an older commercially made one. I could of built my own (did industrial electrical for 6 years) but I got a real good deal on this one. My phase converter is good for up to 145 amps at 240 volts. Biggest single motor I can run I believe is a 15 possibly a 20 hp, but I can run a combo of motors up to a total of 45hp like 9 5hp motors on different machines if I start them one at a time.(going by memory could be a little less total hp) Mine feeds a 3phase breaker panel so its easy to add more machines. I run both my Nazel and my 100lb LittleGiant at the same time off the phase converter with no issues. One problem I did have was the Little Giant had a 208v 3phase motor so running it off the Single Phase 240v with the Phase converter putting out 240volt made it run quite a bit faster so I had to add a jackshaft to slow it down. the 208-240v difference with the Nazel wasn't noticeable. Quote Link to comment Share on other sites More sharing options...
David E. Posted June 2, 2008 Author Share Posted June 2, 2008 Thanks for that good info, its all very helpful. I am such a numpty when it comes to electrics. The hammer is one thing but trying to run a 3ph tig welder from a converter is going to be another can of worms. Thanks again. David Quote Link to comment Share on other sites More sharing options...
Chris Pook Posted June 4, 2008 Share Posted June 4, 2008 Is it an older tig? A lot of newer machines like the Millers can be run 3phase or single phase. Quote Link to comment Share on other sites More sharing options...
nonjic Posted June 4, 2008 Share Posted June 4, 2008 David, The best place for Rotary convertors in the UK is Transwave Power Capacitors in Birmingham. The biggest size they do is 10 hp 3 ph from 240v single. From experience a 10hp rotary has enough shunt to run a 6 hp motor on a 'self contained' type power hammer. ( on a new 'tight' machine, a worn old one will require much less starting torque) Remember that the 3 phases generated by a convertor will be out of plonker, so will upset alot of welding sets - Transwave will be able to advise (they are very helpfull) Quote Link to comment Share on other sites More sharing options...
David E. Posted June 5, 2008 Author Share Posted June 5, 2008 Is it an older tig? A lot of newer machines like the Millers can be run 3phase or single phase. Chris, I haven't replaced my Tig yet, until I know what my supply will be. The Miller machines are almost double the price here in UK, it is almost worthwhile to fly over, buy one and bring back in hand luggage. Quote Link to comment Share on other sites More sharing options...
David E. Posted June 5, 2008 Author Share Posted June 5, 2008 John, can you tell me why there are 10hp single phase motors in the US, when the largest here are 3.5hp on 1ph? I spoke to Transwave, told him my supply details, they could build me a rotary using my 480 volt split phase input,it would have no resale value, but it would give me best supply, pricey tho' ! BTW why cant you do your 25kg on single phase? it uses a 2.2 kw, there are high torque versions of those on single phase in UK. Thanks David. Quote Link to comment Share on other sites More sharing options...
nonjic Posted June 5, 2008 Share Posted June 5, 2008 Hi david, The 25 kg hammer is 3.5 kw. The factory can supply these with single phase 240v motors....... But, my vastly experienced electrician said I would basically be "making a rod for my own back" selling them, ie lots of problems down the line. (not sure if he was refering to the capacitor start on the motors, or folks overloading domestic supplies ) You can buy single phase motor from 'Wyko' (a WEG, very good motors) that would run the 25 kg , not very expensive, or they crop up on ebay often. The pullys & keyways on the chinese hammers are standard, so can be easily swapped over to a single phase motor. Ill get clarification from the sparky next time I see him. Quote Link to comment Share on other sites More sharing options...
Chris Pook Posted June 6, 2008 Share Posted June 6, 2008 (edited) 3500w should be a 5hp motor. (if i remembered the conversion # of 746w=1hp correctly) Lots of 5hp single phase motors running around here on 240v with no issues. Edited June 6, 2008 by Chris Pook Quote Link to comment Share on other sites More sharing options...
David E. Posted June 6, 2008 Author Share Posted June 6, 2008 3500kw should be a 5hp motor. (if i remembered the conversion # of 746w=1hp correctly) Lots of 5hp single phase motors running around here on 240v with no issues. Chris, that is what I can't understand, 3.5hp 240 volt 1phase is about our limit here:confused: Quote Link to comment Share on other sites More sharing options...
David E. Posted June 6, 2008 Author Share Posted June 6, 2008 Hi david, The 25 kg hammer is 3.5 kw. The factory can supply these with single phase 240v motors....... But, my vastly experienced electrician said I would basically be "making a rod for my own back" selling them, ie lots of problems down the line. (not sure if he was refering to the capacitor start on the motors, or folks overloading domestic supplies ) You can buy single phase motor from 'Wyko' (a WEG, very good motors) that would run the 25 kg , not very expensive, or they crop up on ebay often. The pullys & keyways on the chinese hammers are standard, so can be easily swapped over to a single phase motor. Ill get clarification from the sparky next time I see him. Ah ! my mistake John, I thought I read it was 2.2 kw for the 25kg. I shall maybe make enquiries to see if I can get a motor here to power the 25 kg, perhaps off my split phase supply(480volts), might be another sale for you:) A tig like the Dynasty would be big enough for what I want, then this thread would be redundant, thanks all David Quote Link to comment Share on other sites More sharing options...
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