[Kenny Duval]

I was trying to get the G540 hooked to the motor controller to run the spindle and killed the X axis driver somehow. It really would be useful to have some good documentation on setting this up. I was doing it from all the bits and bytes I have found around here and thought I was on the right track but still managed to kill it.

[Fastest1]

Sorry it happened however there is good news too. First of all, you get 4 drivers on the G540, reassign one (most of us can get by without the 4th axis for a while). They are also supposedly easy to physically replace by the end user if I have read correctly.

[Kenny Duval]

I've already go a new one on the way and I'll sending the other in for repair. It's not a big deal just more learning curve. Electricity and I are not friends.

[john-100]

Hi Kenny

not sure how the X axis stepper driver could be damaged unless you accidently disconnected the motor with the power on


the G540's VFD terminals 7 , 8 ,9 are connected to the speed control instead of the speed control potentiometer and are isolated from the rest of the G540 's circuits


terminal 7 replaces the minimum speed end of the potentiometer

terminal 8 replaces the potentiometers wiper

terminal 9 replaces the +10v / maximum speed end of the potentiometer the wiper connects to when the potentiometer at maximum - (fully clockwise )

Note - terminal 9 should be no more than +10V with respect to terminal 7






until the latest version of the G540 it was true the G250 rev2 stepper drivers worked in any position in any G540
(except for a few G540's due to an error in the mother board required one G250 stepper drive re programming to exchange the step and direction inputs )


the new G540 rev8 uses 4 redesigned G250 rev3 drivers that don't have the resonance trim pot - that's now on the G540 mother board !


John

[Kenny Duval]

The resonance pots are on the motherboard in mine. It's out of warranty so I cracked it open and swapped the X and A axis drivers around. The problem remained on the X axis. I moved the X axis cable over to the Y axis and the stepper started moving so I know it's not the stepper.

Looking back I think I reversed the positive and negative coming from the controller to the G540. It was all working before I starting dinking around with it so I know I broke it.

[Kenny Duval]

Further investigation reveals that I am an idiot. There is nothing wrong with it. The opto-isolated inputs did just what they were designed to do. It seems at some point during the day the velocity setting on the X axis got corrupted and that was keeping the axis from responding. I'll have a spare if nothing else or it can go on a lathe my friend just bought it he decides to CNC it.

[Fastest1]

Can I say it? WOO HOO I love free solutions!

[Kenny Duval]

So the plot thickens. Since I think I can read and comprehend I took a 12v 2amp wall wart and went to pins 7 and 9 on the 540. I ran pin 8 to my meter and to ground. When I trigger the spindle in Mach 3 I get a voltage variance between 0 and 10v as expected. However when I go to P1,P2 and P3 on the mill and reset Mach3 I always get half voltage at both locations that's the same. It doesn't seem to matter how Mach 3 is configured. The Mill seems to only put out between 0 and 5v and I always get half of that. I'm stumped on that one. I confirmed that I get 0v on the machine when the G540 isn't connected and the pot is at 0.

Currently anytime Mach 3 is out of reset the spindle runs and never shuts down even after Mach 3 is e-stopped. I have to push the off button on the control panel of the mill.

[Kenny Duval]

Progress. It works sort of this morning. I can set the top speed of 3000 rpm and the bottom at 0. the middle however is not very linear. I have the tach on the Mill but Mach has no way of knowing the speed just yet. I guess I'll need a C3 index card or something to let Mach know what speed it's actually running.

I guess I could possibley grab the pulse at the speed readout on the mill but that would take finding out where to tap and I think Mach wants a single pulse and the mill I think uses 4 pulses and a divider as there are 4 magnets embedded in the collar.

[Kenny Duval]

More progress and more information. When I issue an M3 S3000 the mill spins up the commanded speed and I get 4.20 volts across P1 and P3 and 4.0 volts at P2 and P3. When I issue an M3 S0 I still get 4.20 across P1 and P3. Across P3 and P2 drops to near 0 as expected.

If I issue a command for say S2000 it drops to .5 volts at P2. That seems to all be working as expected except for the fact that issuing an S2000 nets about 100 rpm in high gear. So I think I'm on the right track now but need some fine tuning.

[Kenny Duval]

End of progress. The magic smoke has been let loose. Stupid me. Last of the connections and I went to the wrong end of the connector on the Gecko and shoved a lot of voltage somewhere it should have gone.

Killed the Gecko...for real this time. I also think I killed the motor controller or at the very least the pot.