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As an alternative to buying a pre-made RPC, or completely building one myself, I thought about buying just the panel, and wiring a motor to it. There are two brands available on ebay right now, by Phoenix Phase Convertors, and Anderson Convertors; both are out of Phoenix. A 15hp panel with switch goes for about $300-$400, free shipping. Has anybody heard good/bad or used of either of these brands??
Thanks!
Yeah, your paying them $399 to do the work for you. Post up links please, I want to laugh. But seriously, if you can post a link, I'm REALLY interested in seeing what you get for $400.
If you can read a simple electrical schematic, you can build it yourself. If you can wire a 3 way switch in a residential wiring setting, it should be no problem.
http://www.metalwebnews.com/howto/ph...converter.html
I built a similar phase converter with a push button start and stop years ago, 3hp converter running 3 mills and a lathe, no problem. I WOULD NOT START THEM ALL AT THE SAME TIME! But yes, all 4 have been running at the same time without issue. The lathe is 3hp, one mill is 2hp, the other two mills are 1.5hp bridgeports.
From what I have read running more than one motor at a time actually makes the phantom leg stronger as it is being helped buy all the other motors. I bought a used rotary 3 phase converter on ebay, thinking this was too tough for me to build and it was cheap at $250 ready to go. When I got it home it was a baldor 5 hp motor with the shaft hacked off and I mean hacked.Quote:
Originally Posted by mc-motorsports
Inside the control box was a start capacitor and a mechanical timer. all it did was to tie the capacitor into the phantom leg, just long enough to get the motor up to speed, approx. 1 sec and then it dropped out. The motor then runs on the 2 legs from your service and generates the phantom leg. The phantom leg is usually at a lower voltage, 195 or so on a 220 system. More sophisticated units will have a couple of run caps in the circuit to bring power over from the other legs to get the voltage closer to 220.
I run my Tsugami chucker on this and initially it wouldn't run. The problem turned out to be that the control power was being taken from the phantom leg and it wasn't enough to energize the solenoids.
In a home work shop, you could just run a seperate circuit in for the controls and avoid the phase converter all together for the controls.
Most machines only use the three phase for the spindle motors. On my cnc bridegport, I am using a 1-3 phase vfd.
Mike
A lot of current designs are built on the design by Fitch Williams, look here for the files starting with FRW.
http://metalworking.com/dropbox/_1998_retired_files/
There is one on tuning, which is important if you want balance between the phases.
When I built mine, I used P.B. start instead of timer.
One first rule on hooking up to the machine is to ensure that all single phase circuitry comes off the 240v 1ph legs, and not the artificial phase.
Al.