Warco GH18 VFD version, Wiring diagram i've drawn etc

[Gazz292]

If you bought a GH18 milling machine from Warco in the past year or so, you may have noticed it has a box on the back of the column that sticks out about 150mm.
And operating the mill you might have noticed an a whine to the motor, and that the spindle reverses within about half a second... far too fast for a single phase capacitor start motor to do so usually.

The whine gives it away to anyone who's used a motor on a Variable Frequency Drive before, and if you can decipher that crude and innacurate wiring diagram on the side of the column, you may have noticed the 3 wires to the motor marked U, V and W coming from the 'Transducer Control'

Inside that box on the back of the column is a 1.5KW VFD, and the motor is 3 phase.



This means that in addition to the 6 fixed speeds of the gear head mill, you can also vary the motors speed.


The VFD is set up from the factory so that rotating the knob on the VFD control panel will lower the motor speed... it's set to 50Hz max stock,
The stop/start and direction buttons on the vfd panel do not do anything because it's set up to operate from the push buttons on the control box (that big yellow box that is 95% empty inside, due to not needing contactors and a timer for the single phase motor control)



So i decided to draw out the circuit diagram as it really is and in colour, as well as draw the physical wire routing between the buttons etc, all wire colours are drawn correct as on my mill, so are the markings on the wire terminals.

I've also written up what happens when the buttons are pressed, mostly to show what happens in the milling and tapping modes, but maybe to help diagnose issues in the future.

Finally i've written down all the VFD settings that are specific to this machine, the settings not mentioned are set as listed in the VFD's manual, which is available here:
https://en.ppt-online.org/448529



I hope some of this may be helpful to someone in years to come when the mill is out of warranty.

tho i do wonder if warco know much about this mills drive system, they can't seem to supply me with the motor's real ratings, the plate claims it's a single phase capacitor start motor, 2 capacitors are listed with values as expected for a start and run cap. and the motor is rated at 3HP and 900 watts!!!

[Sea.dog]

Nice work Gazz, but the resolution is much too high so that viewing the images is a pain. Something like 800x600 would be better.

[Gazz292]

oops, i forget that my laptop has a 4K screen resolution.

Resized the attachments so hopefully they display better 

[vtsteam]

Thanks kindly Gazz292 for providing us all with these diagrams! 

(I've reduced them down even further to our forum's nominal 800 pixel full width display requirements. Hope that's okay. I did leave one of the larger images intact as well, since that one had a few small font notes, and they were getting a little fuzzy in the translation --- so there's a duplicate of that one, one at 800 pixels and one original.)