[Hellbringer]

Hi,
I am having one more problem with my setup and i am looking for some input,

I have a old cnc router table that i have upgraded the controller and when ever the spindle comes on the y axis with pluse/move so when i am cutting a circle it comes out as a spiral seeing that the start point and the end point are not the same. X and Z seem to be fine just Y. if i run the program without the spindle the Y Axis is fine and my start point and end point are spot on.

I have tried to change the +/- leads for the servos to a shielded wire thinking that it was picking up an interference same result. the encoder wires are already shielded


Machine Specs

Mach 3
Gecko G320x Drivers
C10 BOB
55V Power supply
Servos (Reused from old setup *replaced encoders*)
US Digital E5 Encoders
C41 PWM Spindle controller
Perske Spindle (Reused from old setup)
Delta VFD (Reused from old setup)
C4 Charge Pump (used as safety switch)

thanks
Mike

[Al_The_Man]

Check all grounding and bonding of the main router gantry frame and the motor frame to a central Earth ground point, make sure the PC case is connected to this point also, including the VFD and spindle motor frame.
Al.

[SCzEngrgGroup]

Do you have the G320X configured properly for the US Digital encoders? You have to enable "HEDS mode", which disables encoder failure detection.

Also, as suggested, make sure your Geckos, power supply, and VFD are all grounded to the same point, with each having its own dedicated ground wire. NEVER daisy-chain grounds.

Regards,
Ray L.

[Hellbringer]

Thanks Guys, but bad news, i have grounded the table (table leg), the gantry (side plate), the spindle frame, VFD, and the computer to earth ground...... just to make sure we had earth ground we went and got a copper rod, drilled a hole in the concrete, and drove the copper rod 4ft in the ground.... still same thing....

Also i do have the HEDS switch turned on

i have also tried used shielded wire for the encoders, servo driver leads, and the signal to the VFD... same thing....

tried to turn the spindle on from the VFD its self same thing.

Here is a video of the problem

[ame=http://www.youtube.com/watch?v=csuiKUjWB6I]CNC Router Problem - YouTube[/ame]

NOTE: i am not moving anything during this video......

Any Suggestions!!

Thanks
Mike

[Hans_G]

you might try disconnecting the encoder cable and wiring encoder A & B to Enc Gnd with really short jumpers right at the gecko. Don't command any motion on the axis, or the servo will run away! Grounding both inputs just makes it look like the axis is holding position & not moving.

If the Y axis stays still with spindle on, my money is on the encoder cable picking up noise.

Edit: to be safe, you might want to disconnect the lead screw from the motor just in case the motor does run away when you enable it. This way the motor just spins and doesn't send the spindle into a hard stop at a high rate of speed. Any movement of the motor shaft with encoders A & B grounded and spindle on indicates the noise is coming from somewhere else.

I've had problems with US digital encoders & noise before. If that's the problem, you might try CUI encoders. I've had better luck with them. They're pretty easy to order from digikey and pretty easy to retrofit as well.