Thread: It's begun....
Aha then I think my theory is right - I have the +ve's tied to XN on the BoB, not the -ve's.
Going to rewire now and hopefully having them the wrong way round the first time hasn't damaged the drivers. A classic Meccano moment if you've ever tried to build that stuff as a kid from the instructions (they deliberately put errors in their diagrams to make you think for yourself ;) ).
I'll report back in an hour or so.
Well it didn't take an hour - the diagram is wrong and the polarities did need swicthing.
Happy days - my machine is moving.
I do have motor stalls though when the steppers have accelerated to a certain speed, so I assume I need some tuning.
Not felt quite like this since I first solo'ed a light aircraft :-)
More as I progress and thanks for the help chaps......
OK, next challange:
I'm now trying to tune my motors and am thinking the following:
My steppers are 1.8degs and I am assuming this is 1.8degs per step, which would mean 200 steps per revolution (360/1.8=200)
My ballscrews are 1605, so again an assumption that 1 revolution of the ballscrew is going to translate to 5mm linear travel
So I am thinking that to get the number of steps per mm for Mach3 I am going to have to set the motors to 200/5=40 steps per mm?
Not sure what the velocity should be set to or acceleration in that case, but I guess I can play with the sliders and get the motors running "smoothly" and not stalling.
Again any advise welcome.
Oops forgot about the driver dip switch setting of 400 steps per rev, so that will be double what the above calc comes to per mm
Quick update and yet another question:
Spent most of yesterday playing with motor tuning, setting soft limits etc and just having fun jogging my machine about the place :-)
Today however I have put in a seperate 32Amp spur from the office workshop consumer unit to a double socket for the VFD/machine and also wired up the VFD. So far so good, as whilst I type my VFD is whirring away with a flashing F00.00 LED display, which I think means its passed its self-diagnostics and is now waiting for me to set it up.
Having burrowed into a few threads I have picked up these settings from a woodworking forum, which seem to apply to a water cooled spindle setup:
Change PD001 Source of Run Commands to '1'
Change PD005 Max operating frequency to 400hz
Change PD004 base frequency to 400hz
Change PD003 Main frequency to 400hz
Change PD006 Intermediate frequency to 2.5
Change PD008 max voltage to 220v
Change PD009 Intermediate voltage to 15v
Change PD010 Min voltage to 8
Change PD011 frequency lower limit to >100hz (120hz to start)
Change PD142 7 Amps
Change PD143 2
Change PD144 3000
Thread here: Tips for Newbie Huanyang VFD users - Page 2
All fo those look sensible?
However, I am pretty sure the 2.2Kw spindle uses up to 11Amps and I have no idea what the PD144 3000 setting is.
Can someone post their 2.2Kw spindle and VFD settings for me or confirm those above are correct? I dearly like to connect the spindle up and get some rotation along with axis movement :-)
Thanks again in advance.
PS. Will try and get some video up soon, as pics don't do an active machine justice:-)
Chris, did you get your brackets sorted how we descused?
Ah yes, thanks - used some 15mm plate again, but this time wide enough to reach the gantry sides - 3 tapped holes and they are now tied into the gantry sides as well as the bottom of the gantry.
Of course I have yet to cut anything to see if they work as intended, but I'm getting closer. Just let the spindle run up to 12,000rpm using the settings above (apart from 11Amps which the VFD was already set for) by setting PD003 to 200.
The spindle is very quiet (certainly quiet compared to hand held routers I have).
Stuck again I'm afraid:
For some reason I am getting an e-stop condition (whether the e-stop is connected to the BoB or not) when I turn my spindle on. Its consistent as well i.e. happens every time.
Can someone confirm my earthing setup:
I have VFD earthed to mains via its own earth connector and also have the shielding for the VFD to Spindle cable earthed to that point (only at that end i.e. shield is not connected to the spindle or machine, only the VFD earth point).
All other control cable shields are earthed back to the star point in my control box (again no connections for the shield on the machine).
I have good mains earth (tested with a socket tester).
Only thing I am not sure about is the spindle's earth (pin 4) is not connected to anything and I haven't connected a lead to it back to anywhere. Also I have earthed the machine via a seperate cable back to the control box star point and have good continuity all the way from the spindle casing down to the frame bed (my machine is nearly all metal).
Oh and I have the Z axis CY cable on the other side of the Z axis plate from the VFD/Spindle cable (about as much separation as I can get.
If your spindle case isn't earthed strange things can happen. It's easy to unscrew the endcap and solder an earth wire in on pin 4, or you could just connect the earth wire to the spindle mount assuming it's metal.
The minimum frequency setting you found, PD11=100Hz, is meant for air cooled motors which burn out when run at too low a speed, due to insufficient airflow. For the water cooled spindles this can be set much lower, however don't expect to get much torque below about 50hz.
PD144=3000 is just a scale factor which makes the rpm display show the correct numbers. You can also set PD14 and PD15 to increase the acceleration/deceleration. They're the ramp-up/down times in seconds, so just decrease them until it's fast enough without faulting.
BUILD LOG: Web Goblin cnc has begunBy Web Goblin in forum DIY Router Build LogsReplies: 147Last Post: 12-02-2012, 07:49 PM