Not only that; if its spinning at a lower RPM than what its speced out to be; the cooling fan wont be spinning at spec and wont extract as much heat as it should, it ends up being a vicious cycle that ends up reducing the service life tremendously
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How many amps is the motor?
Motor running slower than OEM intended is not an issue here 
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you need at least double what the motor is rated for, if you had 18 amps you would require 36 amps power, your drive data sheet says 23.8 amps if Im not mistaken. I wouldn’t attempt to run single phase, just generate a third phase or get it wired in from the pole, then step up or down with a buck boost transformer to meet the motors requirements. Do you need an explosion proof cabinet for the drive?
edit : 13 amps requires 26 amps from the drive.
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seems like a decent approach.
rotary vs static? (asking the all knowing one now…)
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you will want a rotery one, if you want the fuge to run at full hp.
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noticed this up thread.
the $2700 price tag did not stack well against a VFD
on the other hand, something like https://www.mscdirect.com/product/details/09520859 looks viable…
Thank you again sir!
looks like I still need more cutlery…
https://www.ebay.com/i/383032659486 lists as a 7.5HP rotary converter, but states that it will run a 3.75HP motor.
does that mean I need a 10HP phase converter to run a 5HP motor?
edit: that seems to be the case…
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The all knowing one claims that Scotty never uttered the phrase “I cannae get the power captain”.
Yet for some reason that phrase haunts me on almost every engagement…
I hate feeling powerless
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Certainly the low price leader at this point…
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I appreciate the response. I wish it made more sense.
I can get behind “Siemens only”, but you loose me at “drop out”, and suggesting that the motor will “draw too much heat” conflicts with my understanding of electrickery.
Object of the game is to swing this thing as hard as possible, so “drop out” does not sound like what I’m after.
I’d also prefer not to oversize if possible, as all this requires is appropriate sized wires on the front side of the magic, I’m going to keep looking for 5HP options that are rated for single phase input.
Hopefully ABB or Yaskawa has something similar to the gohz unit linked above.
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The shortest explanation I can give to explain @spdking 's point is that vfd’s actually convert AC to DC then use pulse width modulation to output a series of DC pulses that approximates a sign wave. Some brands do a much better job of doing this than others. Lower quality drives typically do a worse job at approximating a sine wave . All of the “noise” outside of a true sign wave generates heat. Typically the quality of the sine wave is worse at lower frequencies because the dc bus voltage runs at roughly 1.4× line voltage and the lower the frequency, the lower the output voltage needs to be. Therefore the lower the frequency, the shorter the pulse. At 30hz the motor requires half the voltage as at 60hz to produce the same amount of torque. If you were to provide the same voltage at 30hz as 60hz the amperage traveling through the windings would double and burn up the motor.
Some 400v class drives can be used on a 200v class motor. This is can be accomplished if you can set the base frequency of the 400v drive to 120hz. Then at 60hz it’s putting out 200v . This is commonly done on woodworking equipment like routers to maintain hp at higher frequencies.
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knew that at one point…but had not seen the connection to @spdking’s explanation. the rest of your translation also makes wonderful sense. thank you!
got any thoughts on the GoHz solution? http://www.gohz.com/5hp-vfd
or do you recommend I call Siemens and ask for their solution?
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To elaborate on your specific situation…very few 400v class drives will run acting as a phase converter. I have never heard of one in my years of automation but have never looked for one either because I have never encountered 400v single phase.
Your ideal vfd is a 10+hp 200v class that accepts a single phase input. If I personally had the exact situation you do, where it appears your goal is to speed up (60hz+) I would run an automation direct gs4. If the goal were to run sub 60hz I would go with a more robust option like siemens. If it were a customers it would automatically get siemens or abb. (I have multiple automation direct plc’s and drives on my personal equipment with no issues ever)
You can not just go by HP and voltage, the actual limiting factor on the drive itself is amperage. A 400v 10hp drive is rated at roughly 15 amps nominal. A 200v 5hp drive is also 15 amps nominal.
If placing the vfd in an explosion proof cabinet I would oversize it even further. Vfd’s produce a lot of heat that isn’t dissipated well in a sealed cabinet. You would be better off remote mounting the vfd in a non hazardous location with adequate ventilation. Typically your EE sizes the conductors going to your vfd to your motor not the max capacity of the drive. It’s not uncommon to see vfd’s derated to 50% or less due to operating environment.
I’ve played with a couple of generic chinese copy drives like the gohz. The biggest issue I have found is a lack of documentation, it’s pretty hard to control one via plc or pc without documentation of what commands need to be sent to which address. If you were to go that route make sure you can control it with your current control system. I would also not trust the rating and go at least one size higher than what they recommend.
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On a rotary phase converter, the HP they are referring to is that of the size of the “idler” motor, not the size of the load capable of being driven off it, which is usually about half the size of the idler. RPC’s “wild leg” or “generated leg” is usually not advised to run control circuitry off of but will start and run a motor load just fine if it’s balanced correctly.
Before I knew what I now know about VFD’s and started using them on my equipment I had built and ran a couple of different RPC’s, biggest one was about 40 HP.
Feel free to PM me if you need some guidance. There are certainly much cheaper options out there than buying a premade RPC especially when you factor freight on a heavy idler motor. There’s a couple of sellers on eBay that just sell the panels with far more reasonable shipping, IMO much easier and cheaper to source a good size motor locally from a surplus shop or Craigslist.
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ABB tech said “all their drives” will do this, but “some will need to be derated”. I assumed that meant most drives could be configured that way.
yeah, I can get 400V DC out of my car, but I’ve not seen 480V single phase dangling from the wall anywhere. I’ve gone looking for 480V 3-phase on more than one occasion, and had to find 600V for a fuge a week or two back…
the concept that I can set the base frequency to 120hz to get 240V out of a drive wired to 480V is an eye-opener, and implies that I had other options than a boost transformer to run that 600V fuge.
even noticed “kits” for building those panels. yeah boat anchors do seem to be relatively abundant, at least in the circles I travel.
thank you!!
I suspect I’m going to take @emdub27’s advice on this one.
Although I prefer to salvage or build when I can.
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I noticed that some drives allow you to change the pulse frequency.
assuming that higher frequency switching leads to “cleaner” sine waves, why would I not turn an ABB from it’s stock 4khz to 16khz every time?