Affordable or DIY 3-phase AC Induction?

[Turn]

If this existed we'd be using it. But since I don't see many posts about it I assume it doesn't.

Any affordable frequency inverters out there, preferably with vector control...?

hey speedy! You mentioned recently you'll be using 0.5hp 3-phase units with inverters that take 120V single-phase and output 3-phase 220V. Can you tell us more about it?

The power supply is free, and AC technology is superior (IMHO) in many ways. But there's a gap to bridge these industrial motors to our domestic needs which I haven't seen filled anywhere by anybody's DIY projects (motion sims, electric vehicles, nowhere). At least not something ready-made and easy to duplicate.

[Riton]

I use this variators frequency in my simulator...
What do you want? build a Variator frequency?

[cthiggin]

This is what I'm going to use for my platform AC type sim.
http://www.automationdirect.com/adc/Ove ... Hz_Control)/GS1_Drive_Units_(120_-z-_230_VAC)

[motiondave]

Could you please tell me where the 240v is free!
I am paying 29c per kwhr for mine

[cthiggin]

IF the question was for me, I don't understand.
IF not, sorry for input.
cthiggin

[Turn]

@cthiggin: Yes, that's exactly what I'm talking about. Thanks, for the link. At $117 for 3/4hp peak...that's got me thinking. Hmmm...

@Riton: which model are you using? Do you have a link? Very interesting blog site, merci! I don't want to build my own, but I might try if a great design were publicly available. I would MUCH rather buy one off the shelf. V/F boxes are 10x more complicated than H-bridges!

Anybody have any affordable 3-phase AC induction motors picked out too?

[Roadster2]

Anybody have any affordable 3-phase AC induction motors picked out too?

The motors are usually cheap enough, it's the Helical gearbox to attach to it that's the expensive bit.

[cthiggin]

Note: Through the help and understanding from my friend Roadster!

I was able to purchase 3 Boston Gearheads, 60:1, 137ft lbs torque - for 450.00 us on eBay - all matching - Retail would have been 3300.00 US - These are new gearheads.
I was able to purchase 3 Marathon 1 hp, inverter duty, 230 V., 3 phase, 50/60 hz. for 369.00 on eBay - all matching, all new - Retail is 287.00 each US.

SO, in summary, I've spent less than 850.00 US for my 3 dof motor/gearhead setup..... was able to purchase a 1.25" spline shaft with spined collar for 110.00 from a Industrial Supply in Michigan, USA. Was able to get a super nice Universal joint, new, for 27.50 from eBay........
I am very happy with my purchases and I will be able to replicate a CKAS "type" platform for 1/4 the cost of the CKAS....

I have learned that you really have to be patient on eBay for the right equipment to show up at the right price............AND, a heck of a lot of research.

As roadster stated: The helical gearheads are just out of sight in pricing - and through my research and talking with several motor / gearhead companies, AND with what I am trying to accomplish, the Worm Drive Gearheads will work fine - reason I went with the Boston Gearheads. Mine are the 726-60-BJ5 Series - for 1 hp at 1725rpm with high output torque.

All submitted IMHO.

Good luck,
cthiggin

[vicpopo]

Hi,
You can watch :
Here : http://www.x-sim.de/forum/viewtopic.php?f=37&t=293
And here: http://www.x-sim.de/forum/viewtopic.php?f=39&t=132&start=160#p2011

Best Regards

[Turn]

Thanks to all who responded.

I've been really struggling with the AC vs. DC question. Now, I'm leaning the AC 3-phase direction. I have a line on a good vector VFD for *cheap* and am about to order 3 of them, but have a question.

Is this line of reasoning right?
-1/4 hp 3-phase 220V AC motor = 186W
-that's 0.85A/phase
-that's 2A of draw from 220V single-phase house wall socket? Or is it 2.55A? Or neither.

This is where I'm confused. i.e. the VFD rating is 4.2A 220V 3-phase output and 10A 220V single-phase input. Why isn't it a 4.2x3A (12.6A) line draw input rating? Similarly confusing to me is why it's rated as a 1hp driver when 4.2Ax220V=1.24hp. ??

I have an AC power slip-ring with a maximum current rating, so for 3 or 4 motors peaking I need to be careful not to exceed it.