VMC15 alternative VFD

[autobus]

Hi,
just strange question up here. I was wondering if I can leave 10HP motor and use Mitsubishi VFD to run that motor?
I line in Poland, want to get rid of the transformer and AMC VFD and get VFD with braking resistor option. I don't need rigid tapping so theretically connecting the motor with HV (460V) and VFD set on 400V it should run...

Thanks

 

[noname777]

Depends on how much you know about this AC motor. Parameters.
-Are you going to interface AC motor feedback and Mits VFD?
-What mode of operation VFD is supposed to be in? just VFD? Vector control or Field oriented control?

The problem here is that you need to have control over speed and torque. More information you can provide to VFD, closer it will run this motor to your RPM setpoint without stalling a rotor.

 

[triumph406]

I installed a Yaskawa GA500 20hp VFD in a 4020 a couple of months ago.

It still needs fine tuning, but works ok.I need to get with Yaskawa tech support (who are outstanding) to get the final parameters correct.

The VFD has an autotuning routine that will auto-tune to match the motor characteristics.

The GA500 has no encoder feedback feature so you can't get rigid tapping, which you say you don't want so likely ideal.

It was $1200 new so didn't break the bank.

If I did it again I would get the Glentek, but at the time I had to spare and was short on $'s

 

[autobus]

It is possible then. Ha! Good.
So, that I don't have much experience with Fadal (most time spending on Fanucs) - how to identify the baldor motor from the plate? Spec/Frame? I understand that the SER stands for serial no.

Most of installations and part availability is US soooo not-very-usable stuff from ebay in our 230V line and 400V phase-to-phase country.
That's why I won't go into AMC/Baldor VFD - transformer must go out. It's a complete rebuild so leaving the motor will reduce costs **a little bit**.

Edit: Judging from Fadal maintenance manual chapter 6 (3.1.1 output 3 phase) looks like that scalar V/f VFD should do. Original control had rigid tapping option installed so it seems that there is normal 5V A/B encoder output on the motor.

 

[noname777]

Register with Mitsubishi and download this course ( attached) . All you need to know how to start. 226 pages of deep speculation how to run AC motor. Highly recommended.

 

[autobus]

Mkay, slight change of plans. I completely forgot about 7.5kW Emerson/TC Unidrive VFD collecting dust on shelf. This beast can run in Servo mode so I could use A/B encoder built in Baldor drive to get RPM instead of calculating freq->speed.
Hope it won't let the magic smoke out

 

[autobus]

I installed a Yaskawa GA500 20hp VFD in a 4020 a couple of months ago.

It still needs fine tuning, but works ok.I need to get with Yaskawa tech support (who are outstanding) to get the final parameters correct.

The VFD has an autotuning routine that will auto-tune to match the motor characteristics.

The GA500 has no encoder feedback feature so you can't get rigid tapping, which you say you don't want so likely ideal.

It was $1200 new so didn't break the bank.

If I did it again I would get the Glentek, but at the time I had to spare and was short on $'s

Just for curiosity - does your machine have the baldor motor? Before connecting drive I'd like to clarify few things such as number of poles - guessing six but seen 4 on OEM Baldors. I'll use the 480V delta connection as the current draw for 230V winding would be way too high for my setup - what values did you use while autotuning? I need to figure out voltage/freq for rated rpm (1760 here).
Apart from spindle, today I did test run with 750W chinese AC servos for XYZ axes - this machine never run so fast. Can't remember what PWM frequency I used on arduino testboard but it really does work nice.

 

[triumph406]

Just for curiosity - does your machine have the baldor motor? Before connecting drive I'd like to clarify few things such as number of poles - guessing six but seen 4 on OEM Baldors. I'll use the 480V delta connection as the current draw for 230V winding would be way too high for my setup - what values did you use while autotuning? I need to figure out voltage/freq for rated rpm (1760 here).
Apart from spindle, today I did test run with 750W chinese AC servos for XYZ axes - this machine never run so fast. Can't remember what PWM frequency I used on arduino testboard but it really does work nice.

It's a 20hp 4 pole Baldor.

The initial values I used came from an old Yaskawa set of parameters. As for auto tuning the VFD did all the work.

 

[autobus]

Mkay, I'll fine tune the parameters as it chirps on lower (sub 800) speeds. Autotuning set the no. of poles to 6, so maybe that's the cause too. Otherwise spinning it to 5k RPM worked flawlessly. Thanks!

And here's the short video of bullying braking resistor and VFD transistors.