Centroid Community CNC Support Forum

Hi All,

I have finally reached the point in my Kitamura CNC retrofit that i can get the spindle turning.
I got a Delta 3.7KW C2000+ (3PH 380v) VFD + PG-01H encoder card. But I'm having some interesting issues....

So My Spindle motor is an old FANUC 2S 2.2 / 3.7KW 200V 4P 1500/8000rpm spindle motor:

Datasheet link: s3.amazonaws.com/Icarus/DOCUMENTS/Fanuc ... s_1791.pdf

So what I tried is to first figure out if this is an AC induction motor or an PM motor. From what I can find (or not find in this case) anything in the datasheet so that made me think it is an AC motor as i feel no "dents" when i turn the motor by hand.

So I connected it all including the OEM Fanuc encoder signals the the VFD.
And then I went through the setup wizard, (immediately went for the complicated method) of including the encoder feedback etc.
When i tried to do a test run it just immediately jumped in OL3 error. I tried some of the advisement in the datasheet such as changing accel time or carrier frequency but that did not help.

So i went back to the basics and just put it in V/F mode. Max output voltage 200V , poles: 4 , max freq 267Hz , base freq 50hz (1500rpm) .
Now when i pressed run it turned, but it did not sound good. The current was around 17A's when it runs with no load on like 500rpm. I tried to set it to higher RPM but the high load pretty much states around. After a bit the VFD throws and overload as it is pulling too much current.

And now... I'm quite lost, any idea what I'm doing wrong? I have worked quite a bit with vfd's and never had such troubles so I'm thinking there is something fundamentally wrong. (this servo spindle worked well with the FANUC drive it had before).

Reset the vfd, did startup wizard, only changed these parameters (bold = default):
P00-10 control method velocity mode
P00-11 velocity mode vf open ctrl
P00-16 load select heavy duty
P00-17 carrier freq 4khz
P1-00 max out freq 250hz
P1-01 motor f base 50hz
P1-02 max out volt 1 200v
P1-10 mid out freq 1-1 3hz
P1-04 mid out volt 1-1 22v
p1-05 mid out freq 1-2 1.5hz
p1-06 mid out volt 1-2 10v
P1-07 mid-put- freq 1 1.5hz
​​​p1-08 min out-volt 1 32v
P1-10 upper bound freq 250hz
p1-12 1st accel time 10s

vid: https://youtube.com/shorts/VwO0N8tdShA? ... FLjQx5ai4V

Just guessing here, but from table 4.1, base rpm of 1500 is at 60Hz. Speed range is 80 to 8000.

So, your base frequency is 60Hz, your max frequency would be 320Hz (60x8000/1500), your min frequency would be 3.2Hz (60x80/1500), and output voltage for every range should be 200V.

I looked at a bit further but seems my vfd is just too light to run this motor with the 380v model limiting the output voltage at 200V for the motor.


Best bet i see so far is to just replace the motor. As the other options would be to reinstate the 380V -> 200V transformer + getting a 200/230V VFD. But the cost of all these options is pretty much the same.

It may be a little small, but it should still run an unloaded motor. Why are you trying to run a 200V motor at 32, 22, and 10V? That certainly has to screw things up. And, the motor frequency is base frequency is 60Hz and not 50.

First thing i would do is set the output frequency to 60Hz and see if the motor turns at 1500 rpm.

tblough wrote: ↑Sun Sep 08, 2024 11:07 am It may be a little small, but it should still run an unloaded motor. Why are you trying to run a 200V motor at 32, 22, and 10V? That certainly has to screw things up. And, the motor frequency is base frequency is 60Hz and not 50.

First thing i would do is set the output frequency to 60Hz and see if the motor turns at 1500 rpm.

In VF mode you have a linear curve of voltage/frequency. I.e. low frequency = low voltage. In other modes there is more of a regulation behind it. But none of those work out and all run into the overload issue. I had a friend tell me they had a simular issue on a retrofit. And in the end they needed a 18kw 380v vfd to drive a 5.5kw 200v motor due to the current spikes.

I tried some autotuning modes on the vfd and they all tell me that the vfd does not have sufficient capacity to drive it at low frequency.

spikee wrote: ↑Sun Sep 08, 2024 11:26 am In VF mode you have a linear curve of voltage/frequency.

Are you sure about that?

tblough wrote: ↑Sun Sep 08, 2024 3:18 pm

spikee wrote: ↑Sun Sep 08, 2024 11:26 am In VF mode you have a linear curve of voltage/frequency.

Are you sure about that?

Small update:
I "solved" this by swapping out the motor. Due to the motor being 200V and my Delta C2000 being 400V there was just too much de-rating needed.
Another option could have been to get a bigger delta drive (7.5-11kw) but that would have cost more than swapping this whole thing. So that is what i did.