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Re: Balancing rotary phase converter to run three phase VFD. I honestly have not looked into it as much as I should, so I honestly cannot answer with certainty. I'll let others chime in on that.
Re: Balancing rotary phase converter to run three phase VFD.
Re: Balancing rotary phase converter to run three phase VFD. Yes Dave Originally Posted by forhire Oscar, are the run caps on the left and start caps on the right?
Re: Balancing rotary phase converter to run three phase VFD. Oscar, are the run caps on the left and start caps on the right?
Re: Balancing rotary phase converter to run three phase VFD. A three phase running on single phase and no converter and no capacitors has 60% power but running at the same speed. Adding a motor and or capacitors will bring the power 100%. But most machine tools never use more than 30% power. A drill press will use 100% and welders need balancing for the DC power. Dave Originally Posted by Brand X Exactly, like my mill does now.. Just want a larger motor, and a switchable run caps to balance the twin motors out somewhat..That is the versatile part of this way of doing things.. No one large motor to start makes for a easier time to get things going.. Really need nothing more then I have now, and is sweet running the 60i at full tilt.
Re: Balancing rotary phase converter to run three phase VFD. Exactly, like my mill does now.. Just want a larger motor, and a switchable run caps to balance the twin motors out somewhat..That is the versatile part of this way of doing things.. No one large motor to start makes for a easier time to get things going.. Really need nothing more then I have now, and is sweet running the 60i at full tilt.
Re: Balancing rotary phase converter to run three phase VFD. Find a start wound motor and switch on after phase converter has started will boost the power. Dave Originally Posted by Brand X That;s fine but old transformer 3 phase stuff is excellent welding machines over most single phase tranny units. It when I want to run dual shield out of my LN-25 pro, so not running it all that much.. Just when needed. I had pretty much most single phase standard type,also Choppers from Esab/Lincoln, and Miller. Inverters from many places, and all I have left now. Just want one quality tough as nails 3 phase Transformer unit..Running off my phase converter. $250 for the multi $1000.00 unit will force me to upgrade my rotary's output..
Re: Balancing rotary phase converter to run three phase VFD. Originally Posted by smithdoor I tried to keep all single phase and only used the phase converter when need. It makes life simple just flip a switch. Dave That;s fine but old transformer 3 phase stuff is excellent welding machines over most single phase tranny units. It when I want to run dual shield out of my LN-25 pro, so not running it all that much.. Just when needed. I had pretty much most single phase standard type,also Choppers from Esab/Lincoln, and Miller. Inverters from many places, and all I have left now. Just want one quality tough as nails 3 phase Transformer unit..Running off my phase converter. $250 for the multi $1000.00 unit will force me to upgrade my rotary's output..
Re: Balancing rotary phase converter to run three phase VFD. Thank you for photo. They are using a timer to turn off the starting capacitors after a few seconds. Witch replaces the starting relay but dose the same job of after the converter Dave Originally Posted by Oscar
Re: Balancing rotary phase converter to run three phase VFD. That is simple Just oil capacitors and starting capacitors. Just look at the wiring diagram I posted 📫 Dave Originally Posted by Oscar
Re: Balancing rotary phase converter to run three phase VFD. Originally Posted by smithdoor I tried to keep all single phase and only used the phase converter when need. It makes life simple just flip a switch. Dave Simple is boring. Different, exciting, unique. Much better than boring.
Re: Balancing rotary phase converter to run three phase VFD. I tried to keep all single phase and only used the phase converter when need. It makes life simple just flip a switch. Dave Originally Posted by Brand X I think it would be more of a benefit for me, running the Esab I just picked up.. Still a two motor RPC setup is more versatile,and easier to deal with power input issues. Huge difference running these three phase, over inverters machines on a RFC..
Re: Balancing rotary phase converter to run three phase VFD. Originally Posted by Oscar Didn't have a chance yesterday; got home late from Hooters I'll do it tonight. I think it would be more of a benefit for me, running the Esab I just picked up.. Still a two motor RPC setup is more versatile,and easier to deal with power input issues. Huge difference running these three phase, over inverters machines on a RFC..
Re: Balancing rotary phase converter to run three phase VFD. Originally Posted by forhire That would be great! Didn't have a chance yesterday; got home late from Hooters I'll do it tonight.
Re: Balancing rotary phase converter to run three phase VFD. Good! Most of the applications I deal with we double the size of the drive but we're also asking a 10-20 HP motor to ramp up in seconds to maintain flow. In your application, you should be able to play with feed rates and cutter styles to minimize amp draw. Sent from my SM-A115AZ using Tapatalk
Re: Balancing rotary phase converter to run three phase VFD. Originally Posted by bubmiller I've never seen a drive that couldn't be run on single phase? I have it working on single phase. I removed L2 and moved L3 to L2 on the VFD. Spins right up. No errors. Unloaded I'm drawing 3.5A. It will be interesting to see what it draws while cutting. The drive is rated for 11A. With derating (1.73*FLA) I'd need a drive capable of 16A to get the full 9.5A FLA of the spindle motor. Honestly, I doubt he'll ever see over 50% load. It's an ER25 spindle running small cutters in hardwood. This would have saved me a lot of time had I simply tried it on single phase from the get go. Of course I've learned a lot along the way.
Re: Balancing rotary phase converter to run three phase VFD. It how much you want to spend on way to go. All the commercial rotor phase I seen used a start wound motor and a capacitor start and or run. Most the third leg are unstable. The vdf is electronic type the frequency will very and if one part fails now you have a new anchor ⚓. The last is build it your self and save a lot of cash and have a more stable third leg by not trying to push the idle/generation motor. Dave Originally Posted by forhire I suspect your correct. The drive is an EMS (Yaskawa) VS-606PC3 (Vari-Speed) based drive, model CIMR-PCA23P7. I have Yaskawa Vari-Speed drives in my TC3 and I know guys on the forum have successfully ran them off single phase. The manual doesn't list an option to toggle phase loss detection. It would be easy enough to try. It would certainly simplify the machine and likely be cheaper to run.
Re: Balancing rotary phase converter to run three phase VFD. Originally Posted by bubmiller You're correct, there is not a parameter for that. The manual does say not to use L3 for single phase use. That would tell me that L1 and L2 run the control side of the drive. Not sure if the drive cares about the third leg, or if that setting is hard coded in the program. I had read that also. Looking at the machine schematic I will need to swap L2 and L3 at the VFD, as the machine is setup for L1 & L3 on the control side. Derating might be an issue if it's run hard, but I doubt that will be the case. The spindle is 3.0 kW and the drive is 3.7 kW... a proper 1.6 to 1.7 derating would suggest I'd need a drive around 5 kW. A spindle on a little machine like this isn't like running a fan or a pump. I'm hooking up the PC this afternoon. I'll try it on single phase and see how it does.
Re: Balancing rotary phase converter to run three phase VFD. I'll upload them today after work.
Re: Balancing rotary phase converter to run three phase VFD. Originally Posted by Oscar Forhire, My 30HP RPC has unloaded voltages balanced within about 2-3%, but I did not build it. I can take detailed pictures if you'd like. That would be great!
Re: Balancing rotary phase converter to run three phase VFD. Originally Posted by forhire I suspect your correct. The drive is an EMS (Yaskawa) VS-606PC3 (Vari-Speed) based drive, model CIMR-PCA23P7. I have Yaskawa Vari-Speed drives in my TC3 and I know guys on the forum have successfully ran them off single phase. The manual doesn't list an option to toggle phase loss detection. It would be easy enough to try. It would certainly simplify the machine and likely be cheaper to run. You're correct, there is not a parameter for that. The manual does say not to use L3 for single phase use. That would tell me that L1 and L2 run the control side of the drive. Not sure if the drive cares about the third leg, or if that setting is hard coded in the program. Sent from my SM-A115AZ using Tapatalk
Re: Balancing rotary phase converter to run three phase VFD. Forhire, My 30HP RPC has unloaded voltages balanced within about 2-3%, but I did not build it. I can take detailed pictures if you'd like.
Re: Balancing rotary phase converter to run three phase VFD. Originally Posted by bubmiller I've never seen a drive that couldn't be run on single phase?? Find the parameter list for the vfd, and turn off the error code for third leg sensing. Most brands want you to use inputs L1 and L3. A drive rectifies to DC voltage anyway, so the difference between inputs is for error reporting. I suspect your correct. The drive is an EMS (Yaskawa) VS-606PC3 (Vari-Speed) based drive, model CIMR-PCA23P7. I have Yaskawa Vari-Speed drives in my TC3 and I know guys on the forum have successfully ran them off single phase. The manual doesn't list an option to toggle phase loss detection. It would be easy enough to try. It would certainly simplify the machine and likely be cheaper to run.
Re: Balancing rotary phase converter to run three phase VFD. I've never used oil run capacitor for the starting circuit. Its always been high mf starting caps for the rotary starting circuit with 2 contactors and a timer or potential relay to kick out the start caps so they dont stay in the circuit too long and blow. I guess it could be done though, just would take a lot of them. I balance it by putting run caps inbetween all 3 phases L1 to L2, L2 to L3, and L1 to L3. I always use L2 for the made up leg. When the phases were unbalanced the idler motor was "noisy" After getting it more balanced it quieted down while running. I would assume the correct capacitance with the motor field inductance it makes the phases closer to 120 degree vectors and pulls the rotor around properly and not favoring one set of motor coils more than the others. That was the "noise" i was hearing and seeing when unbalanced. I've also read that high efficiency smooth shell motors are not as good as the old cast iron finned motors for converters. I would think this is for heat dissipaton as unbalanced would cause more heat. I also looked for high service factor motors as they can take more abuse.
Re: Balancing rotary phase converter to run three phase VFD. here is simple best way I found works ever time Dave Originally Posted by forhire Dave, is the purple column, on your chart, the amps of the run capacitor bank? I understand they are not needed. I'm simply trying to understand all the numbers. I'm going to start building my 10 hp unit so I get more experience.
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