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Estop after turning on spindle
« on: November 01, 2015, 03:19:51 PM »
New machine build.   I know there's probably a crossed wire or something but I don't know how, it's pretty simple so far.   Using a g540.  Everything works until I turn on the spindle, then it's estop.   Pictures attached to show how simple my machine is so far.   Can't imaging what would be crossed?

Re: Estop after turning on spindle
« Reply #1 on: November 01, 2015, 03:21:15 PM »
By the way, the spindle is in no way attached to the gecko...

Offline mc

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Re: Estop after turning on spindle
« Reply #2 on: November 01, 2015, 04:36:19 PM »
Most likely interference from the spindle, which is causing a small voltage to be generated in the E-stop/limit wiring.
The VFD to spindle wiring should be shielded, as that is a major source of noise/interference, which will be picked up by any nearby wiring. If that wiring is low voltage (5V or less) control wiring, it can be enough to generate enough voltage/current in that wire to trigger inputs, especially things like e-stop or limit switch circuits. It also has the potential to cause missed/extra steps in motor drivers.
Re: Estop after turning on spindle
« Reply #3 on: November 02, 2015, 07:58:28 AM »
I checked, it's not the lack of wire shielding.  I took the spindle out of the mount, held it in my hand, turned it on and of course everything still worked.  However, when I just touched the side of the spindle to ANYWHERE on the machine, it throws an EStop.  Obviously the spindle is somehow grounding out the EStop.  Thoughts, ideas?  I'm stuck.
Re: Estop after turning on spindle
« Reply #4 on: November 02, 2015, 08:18:30 AM »
Set the debounce in mach3 up to like 2000 and try it.... if if that helps it's most likely a noise problem.... go through and make sure all connections are tight.... especially grounds.  just some ideas to try
Re: Estop after turning on spindle
« Reply #5 on: November 02, 2015, 08:59:59 AM »
I suspect you have an issue with a ground loop. When the spindle isn't mounted you've broken the ground loop.  VFDs produce leakage currents in the motor that must be continually be drained off. Look for multiple paths to ground in your wiring.
Re: Estop after turning on spindle
« Reply #6 on: November 02, 2015, 11:55:12 AM »

That's what I'm thinking.  But if the spindle is grounding the machine, I don't know how to fix that?  I mean, the connection to the VFD is pretty simple, 240 to the wall and 4 wires to the Spindle.  When the 4 wires are connected to the spindle and the spindle's connected to the mount, it grounds out.  Is there somehwere in the spindle that one of the 4 wires connected grounds to the spindle casing?
Re: Estop after turning on spindle
« Reply #7 on: November 02, 2015, 07:12:52 PM »
I looked at you pictures.  If you want a safe reliable machine you need to follow good wiring practices.  Those open wires from the VFD to the spindle are antennas radiating RF over your whole neighborhood!  Probably knocking out TV reception, interfering with wireless phones etc.  Everyone hopes you'll give up on this machine so they can go back to what they were doing.  Only half kidding here.

Your stepper motors also do the same kind of thing, they operate at pulse rates up in the Kilohertz range too. So you should be using shielded cables from the Gecko drives to each motor.  You should use shielded cable from the VFD to the spindle motor too.  The important thing is to create just one ground bar for ALL grounds, including the power cord ground.  Do NOT jump a ground wire  from one device to another and then to ground. Take ever ground from the device straight back to that one ground point.  Important point here.  For anything mounted to a grounded surface, that would be motors mounted to the frame of the machine, do NOT connect the shield from the cable to the motor, insulate it from touching ground at the motor.  The other end of the shield should go to that one ground point.  The frame should have one wire going to that ground point.  For the spindle motor make sure the ground wire for the motor goes all the way back to that ground point.  Do NOT connect the cable shield at the spindle. Insulate it from touching ground, tie the other end to only that one ground point.  All the shielding so far is about keeping the noise from the motors, and drives from getting out.  

You also want to keep noise from gettting in to signal wires.  Use shielded wires here too.  Connect the shield only to that one ground point. Do NOT connect any shields or grounds together to get back to the one ground point, always use a separate wire.
Where you have individual open wires always twist the RELATE wires together in a nice tight spiral up to as close to connection points as you can. This acts as shielding too.  PLAN your wiring routes and neatly route signal wires away from power wired everywhere you possibly can.  If they must cross, do so at right angles with as little wire near one another as possible. Never route signal and power in the same wireway if at all possible.  If you can't avoid it, use only shielded wires.

"I'll neaten it up after I get it working" is WRONG!!!  There is a strong possibility you will never get it working because it is sloppy and wrong.  You also won't ever be able to make it neat because you already routed it wrong and the wires won't reach.  You did OF COURSE make a wiring diagram BEFORE you started wiring, right?  I'm guessing you aren't the kind of expert that can look at a mass of wires and see the wiring diagram in your head.  So why would you try to do this without one?  And just so you know I did wire my own machine without a wiring diagram!  It was stupid even for me. However I have been building control panels for a little more than fifty years, so there is a pretty good chance I know how it work.  You'll notice a pile of cut off wire ties as I work.  That is because I tie everything down as I go.  When I add more wires I cut out the first ties and replace them.  My panels start out neat and stay that way right to the end as a result.  I buy cheap ties to start and when I am done they are are high quality ones.

Got it?
Re: Estop after turning on spindle
« Reply #8 on: November 02, 2015, 09:11:03 PM »
Couple things, bumping the Debounce up fixed the issue, thank you!  Yes, I know my wiring is pretty lame, but this machine is more of a proof of concept at this point than anything production grade.  Yes, the plan is to go back and do it again, I will probably use this machine to make parts for the next "planned" machine.  I know it's sloppy to say the least, but I'm just happy I have a functioning CNC at this point.  As for the wiring, you should have noticed I have almost none.  I have the 4 wires from each motor in a harness of sorts that connects to a DB9 cable.  I bought nice cables online that weren't cheap.  That runs to the G540, the only really sloppy thing imho is the wiring from the VFD to the Spindle, yes, it needs to be redone correctly and I  full plan on it. 
Re: Estop after turning on spindle
« Reply #9 on: November 02, 2015, 09:11:30 PM »
By the way, thank you for your help!  And I can only hope that I'm jacking up the neighbors wifi. =)