Can This Yaskawa Vfd Be Used For Single Phase?

The VFD on my lathe is set to just ramp up to line frequency (50hz hear in uk) which gives a very nice soft starting. I just use the gear box to change the speed to retain full torque.

I've used the variable speed function on the mill for power tapping as the lowest gear setting was still a bit fast for my liking, also the nice gental start up / stop makes it not agressive on the tooling when you reverse it out.

Also on the mill i pushed the frequency up to about 65HZ for a little more top end speed with tiny tiny mills and drills which can be handy (the motor on my mills marked 50/60hz) I think if you speed them up too much the cooling fans take more resistance to turn at the higher speeds although I only ever encountered issues with motor warmin when running it under speed for slower RPM as the fan dosn't push enough air to cool it.

My lath motor smoked out when I first set it up (unbeliveible the insulation broke down a bit after 60 ish years :) ) I asked the rewind company to wind it for 220v (it was marked 220/440) which they did and it's been running sweet ever since. Did cost about the same as a new motor(probably a china brand new motor) but I didn't have to change the mount or pullys so saved a lot of hassle with that side of it and it looks kinda 50's sci-fi which is just a side bonus :)

Stuart
 
Beast of a motor in that machine for 3Hp.

I have installed VFDs on RPC systems without any issues, but I am no expert on the subject. The newer RPCs are very quite, and work well, but I can see that you would be better off just going with a single phase VFD. I would call the manufacturer of your VFD and see what they recommend, but at the end of the day, I think you are better off selling the Yaskawa and getting a single phase 3 Hp unit. You may get more for it than a newer single phase VFD unit. On older motors, insulation breakdown is definitely a problem with VFDs as Stuart mentioned, and you can get a very decent quality newer 3 phase motor for not much. I would try to stay with one that is at least inverter rated. When I spoke to a few manufactures about their inverter rated motors and operating parameters, most mentioned that the bearings in their 1800 RPM are good to 2X their rated speed, cooling can become an issue at the higher speeds (and very low, below ~15 Hz for a TEFC type, TENV can run lower). As far as operating range, a reasonable operating envelop is something around 20-80Hz for a newer 3Hp TEFC motor, possible 90Hz. You still need to be able to change mechanical speeds to be in an operating range of your motor. I set my system up so 60Hz will turn the lathe spindle the same speed it previously ran, then one can swing up or down with in any mechanical speed window. If you needed slower speed range, then I would set the lathe spindle speed for each gear so it operates at its rated speed at say 80Hz. Torque should remain pretty flat below the motor base speed, HP declines in a linear fashion, above the motor base speed, the opposite occurs up to abut 90Hz. This varies by motor and rating. Lathes that come with factory VFDs in this size range often have 2 speeds, the VFD controls a ~8-10 fold speed window, so something like 40-400, 400-2500. They also use oversized motors and motor cooling fans to achieve these wide operating windows. Just a starting point.
 
I did review the manual for the J1000 VFD, it is rated at 3KW light duty, 2.2KW heavy duty on 3 phase input. Running a 3P 3Hp motor using single phase input on a J1000 VFD in would require a 5Hp unit something like a 2A0020B. Heavy duty is also considered running the carrier frequency higher, which I normally do because of motor whine. So probably would need a different model or replace the RPC.

Not sure what motors are available in Canada and shipping/customs, but the two places in the US that I often use for motors would be Electric Wholesale Motors and Dealers Industrial Equipment. The latter has some nice motor/VFD packages, unfortunately the Canadian exchange rate is not very good these days. Could drive across the border to pick up something at either of these companies. Some 3Hp models and Teco N3 VFD.
http://www.electricmotorwholesale.com/LEESON-171320/
http://dealerselectric.com/N0034C.asp
http://dealerselectric.com/N3-203-CS-U.asp

Hope this helps, it is rarely simple.
Mark
 
You had said about installing the pressing machine when you were talking about the VFD . I figured you were running A Vacuum with the VFD.
Most pressing machines use a vacuum to dry after the steam.
 
600V 3-Phase is somewhat common in the US for large industrial applications. They often utilize motors listed as 575V as that is the utilization voltage. It is also somewhat common for the utilization voltage stamped on motors to be 5-10% less than nominal voltage anyways as it accounts for some level of voltage drop.

For example, most single phase service is 240V between the phases, even up to 245V+, yet most motor nameplates list 220V or 230V.

Same goes with 120V, many items are marked 110V today yet most of us get 120V or 125V from a phase conductor to neutral on a single phase or 208Y service.

A 575V motor should work just fine on a 575V or a 600V service

Not completely relevant to the conversation since we are discussing a VFD (of which I have little experience with) but thought I would just add regarding the funky looking 575V motor.

---Aaron
 
David VanNorman said:
You had said about installing the pressing machine when you were talking about the VFD . I figured you were running A Vacuum with the VFD.
Most pressing machines use a vacuum to dry after the steam.
Click to expand...
Ahhh! Now I understand. You seem to have some experience in this industry. For the machines that we're selling, there is a VFD on the fan blower motor that fills up the garment after steam has been applied.
 
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