VFD tuning for a Marathon motor

cut2cut

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I need some advice tuning my VFD to my inverter motor. I've been running it at 60HZ but wish to run the VFD at 120HZ for double the rpm.

I have a Delta VFD-E ( 230V ) and a Marathon Inverter motor ( this is a different motor than what came with the mill ). Its working "ok" with the original default settings ( that were for the original motor ) at 60HZ but I just replaced the spindle bearings in my mill so they can now handle 7000 rpm ( with my 2-1 ratio pulley ). At 60HZ my motor turns at 1750 rpm and with the gear ratio I'm achieving 3500 rpm at the spindle. I want to run the motor at 120HZ so I can get 7000 rpm maximum *spindle rpm ( which is 3500 rpm on the motor )

The VFD manual suggests I need to alter the mid point Frequency ( section 4-48 / parameter 01.01 ) . I'm not sure what to set it to. Also, when I attempted to set ( section 4-49 / parameter 01.05 ) to 2HZ the VFD error-ed and it auto set it back to the default 1.5HZ. The range is supposedly .1 HZ to 600HZ, so it must have some override if other settings aren't correct. I'm just not confident I can figure this puzzle out myself and hopeful someone experienced can lend a hand.

enclosed are pictures of the Motor's specifications and also the VFD manual settable parameters for tuning the motor.

And a link to the VFD manual is here :

http://www.delta.com.tw/product/em/.../manual/Delta_IA-MDS_VFD-E_UM_EN_20140912.pdf

Jake

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Maybe your drive is more complicated than the ones I use, but on mine I simply have to set the max output frequency to whatever I want, in your case 120hz.


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Please see the attached basic parameter changes. The upper frequency is set by parameter 01.00. The Fbase is the base frequency of the motor or 60Hz, the mid-point I would leave at the factory default, this is not the half way point in the frequency range. Often two parameters will be tied together, so something like the minimum output 01.05 needs to match the motor minimum output 01.28. The motor type and load need to be entered into the MOTOR 1 parameters, the default poles is 4 for a 1750 RPM motor. The default PWM frequency 02.03 is 8kHz, if you have a lot of motor whine this can be set to 12kHz. There are a number of other parameters that may need adjustment depending on the control inputs and to do some tweaking.
Delta VFD motor parameters .jpg
 
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The motor plate shows it will go to 5400 rpm safely, so you could run it to 180 HZ to achieve that. Whether that is a good idea or not depends on other factors, including the spindle bearings. You did not mention what kind of mill it is. Sometimes there are other parts of the machine that will also limit the speed, like perhaps a variable speed drive. Make sure everything can handle the additional speed.
 
That is a nice motor/drive combination.

In addition to what @mkjs said above, I would set up the drive for Vector Control 00.10 = 1. much better torque control, and overrides some of the setup parameters.
 
Please see the attached basic parameter changes. The upper frequency is set by parameter 01.00. The Fbase is the base frequency of the motor or 60Hz, the mid-point I would leave at the factory default, this is not the half way point in the frequency range. Often two parameters will be tied together, so something like the minimum output 01.05 needs to match the motor minimum output 01.28. The motor type and load need to be entered into the MOTOR 1 parameters, the default poles is 4 for a 1750 RPM motor. The default PWM frequency 02.03 is 8kHz, if you have a lot of motor whine this can be set to 12kHz. There are a number of other parameters that may need adjustment depending on the control inputs and to do some tweaking.
View attachment 231054

wow. Thank you @ mksj. I'll try those settings

I have noticed the motor whine a bit, so I'll try adjust the PWM frequency too. I race RC cars, so I'm familiar with tweaking PWM but the speed controls for RC are far more "user friendly" / simple so outside of timing manipulation these VFD's are more complex beasts. btw, I falsely thought that Motor 1 settings might be just a series of presets. ( Motor 0, Motor 1, Motor 2 ).

I received an over voltage fault while lowering the rpm, so I am told I need to increase the deceleration time parameter.

@ Jim, does Vector control require feedback from the motors encoders ? Or is this just a setting. Its becoming more and more apparent that I should look in the manual a little deeper ( understatement of the year ! ). I actually have a durapulse VFD that I plan to use, which has a feedback encoder card.

@Bob, I just got done installing Angular Contact Bearings in the spindle that should be good for 7k rpm. At this point, due to the gear ratio, I think if I used a higher frequency I'd lose too much torque and don't really need more rpm. If I need that sort of rpm, I'll probably get a 20k rpm high speed spindle to attach to the side of the head of my mill. In fact, that is something I thought to do someday.

Jake
 
@ Jim, does Vector control require feedback from the motors encoders ? Or is this just a setting. Its becoming more and more apparent that I should look in the manual a little deeper ( understatement of the year ! ). I actually have a durapulse VFD that I plan to use, which has a feedback encoder card.

It depends on if it is a sensorless vector drive. I may have been making a bad assumption on that count, the Delta may or may not require an encoder. I didn't try to wade through the entire manual.

The DuraPulse is a sensorless vector drive with an easy to use autotune feature. I have one on my mill and am very happy with it. Speed control and constant torque are great, especially at low RPMs.
 
It depends on if it is a sensorless vector drive. I may have been making a bad assumption on that count, the Delta may or may not require an encoder. I didn't try to wade through the entire manual.

The DuraPulse is a sensorless vector drive with an easy to use autotune feature. I have one on my mill and am very happy with it. Speed control and constant torque are great, especially at low RPMs.

The only reason I haven't installed the Durapulse drive yet is because it physically is a bit larger requiring some "adjustment" to my electronics cabinet. hmmm, ok, I'll look into it now as you are making it look like I should just jump in and get that done sooner than later! :)

Cheers,

Jake
 
The one thing on the Durapulse is the braking resistor function, in order to turn it on, it is cryptically labeled '' overload protection'' in the manual. Required a call to tech support to figure that one out. ;)
 
The one thing on the Durapulse is the braking resistor function, in order to turn it on, it is cryptically labeled '' overload protection'' in the manual. Required a call to tech support to figure that one out. ;)

I do have the braking resistor, so this is certainly good to be aware of ! Thank you
 
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