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AC drive will run a 60hz motor but not a 300hz one?

tomjelly

Stainless
Joined
Aug 26, 2007
Location
GA
I have a giordano columbo 300hz 18000 rpm 220v 3.7kw 5hp spindle motor that came on a router with a hitachi j100 inverter drive and were working until put into storage a few years ago. I'm retrofitting the control.
I returned all F settings and A parameters back to factory supplied values as in the vfd manual, but poles set to 2. (reset because the spindle motor would not start when trying to test it manually with the drive key pad after the original PLC was removed and I could not raise the frequency past 60hz, which I thought was why the 300hz motor would not run)
I attached a conventional 3 phase 3450 rpm 60hz 2hp motor and the drive worked fine, varying the speed no problem. With the 300hz 18krpm 3.7kv 5hp spindle motor it will only turn at an eyeball estimate speed of 40-60 rpm no matter what frequency or how many poles I set the drive to (tried 60-300hz range as indicated by the drive readout, rpm stays the same 60 or so rpm) I even tried it with another, identical spindle motor with the same result (both spindle motors test with same resistance pole to pole and no continuity from any pole to ground).
As this unit was used with this specific spindle motor before being put into storage I'm baffled. 18000 rpm=((120x300hz)/2 poles) so I have the poles right I think. The only other issue is "err" which shows in the display between f14 and f1, error 7: "when the converter voltage exceeds a certain level due to regenerative energy from the motor this protection function engages and the output of inverter is cut off" I don't see how to reset the error, but the unit functioned fine even with the "err" showing when testing the conventional motor, and does rotate the spindle motor (although slowly). The j100 is rated for 200-230v input, and I am running this a little higher on a rotary phase converter with phase voltage ranges of 240 to 256, but that doesn't seem like the issue for this error, and again the error seems to have no effect on the unit running the 60hz motor.
Any suggestions?
EDIT: I changed "base frequency" parameter to 300 from the oem setting of 50 and now its working. there was no explanation of base frequency in the manual at all, maybe it was set to 50 because that is the japanese standard line frequency? whaddya know, the error went away as well and its working fine...
 








 
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