Denford Software & Machines

Hi All, I am a new owner to an old Orac lathe, I intended to refit the controller to Mach3 and need help on the Spindle VFD.

The machine came with a big KEB VFD as shown in the attached photo, does anyone have the wiring and configuration details on this device? I searched through the posts seems the one I have is a different type to the typical. I also wonder this VFD accept what kind of signals, will it work with Mach3 PWM or 0-10V?

If necessary to change the VFD, what type of VFD shall I get to work with the spindle motor?

Thanks a lot for any help!!

Cheers, James

It should work fine with a 0-10v feed, for wiring connections have a look at the Mirac schematic. I'm fairly sure this inverter is used in the Mirac.

angel-tech wrote:It should work fine with a 0-10v feed, for wiring connections have a look at the Mirac schematic. I'm fairly sure this inverter is used in the Mirac.

Thanks angel-tech! I searched all the KEB Combivert here and the net found no information, seems the one I got is different perhaps it is the oldest model (older then F0). Anyway, I have tried to connect it with 0-10V to REF and COM, and combination of COM, 5V, 12V, open to F. The motor just doesn't move at all, there are no voltage at UVW, but there are some voltage from the motor when I turn the spindle, so I think the motor is still good, just the inverter needed attention. However there is a 16 pots switch on the inverter, but couldn't find any information on it, or I should use another VFD.

Dosn't the PCB silkscreen give you a clue as to the terminals ?
Can you take a close up of the right hand terminal block... there may be an enable or run input required - you will probably find a vref,com and speed command input which you could wire up to a potentiometer for testing

To start the spindle you need to connect the drive enable and supply the drive with a 0-10v signal. Did you find the Mirac schematics.?

Thanks Admin and Angel-tech! The attached photo is the right side terminals, the labels are very clear, the wiring was connected to PC1951 with REF, COM and F three wires only. I did try connect the CRF, REF, COM with a 10K pot, and also tried REF, COM to power supply (0-10V), together with F connect to COM, open, +12V etc., none of these connection give any voltage to the UVW motor output.
However, to the left of the terminals is a 16 ways selector, there may be wrong setting of this switch, but after many time search on the net still unable to find the instruction of this Combivert model.

This page from another KEB drive shows two ways of wiring the inputs - with an external supply or using the internal.

The terminal names look similar - at least you can see how the pot should be wired - I'm not sure about the F and R inputs...at a guess there will be voltage on FRQ which can be switched to F or R to run forward or reverse. FLT could be an internal relay which switches on error / zero speed etc.. depending on setup.
I'd also guess that the 16 way switch will be a mode/setup selector so you really could do with finding some info on that

ok to test this, connect crf to ref, and f to 0v, that should give you full speed.

For Mach3 use you connect a 0-10v (probably isolated) feed to com and ref, and use a relay to connect f to 0v for the enable.