Re: [CAD_CAM_EDM_DRO] length of step/dir lines G340

carlcnc@... wrote:

> I have seen several past posts regarding problems with the encoder
> signals o Gecko 320/340's.
> HAs anyone tried locating the amplifier close to the
> servo to reduce the length of encoder wires?
> Would this reduce the problems with "noise"?

Possibly, but it would also mean making the wires from the computer to
the gecko drive longer. Since those are opto-coupled at the gecko's
input, that might not be a problem at all. So, maybe mounting the gecko's
in a box on the back or side of the machine, so the encoder wires were
just long enough to provide slack and have all the drives in one box
would be best.

> Of course it could mean you need some capacitors located close to the
> GEcko,and maybe some "help" for the step/dir signals.
> How far from the supply can I locate Gecko 340?

You probably want all the Gecko drives and the power supply in one
box.

> 2',4',6',? For my gantry it could be as much as 8' of cable carrying
> 70-75V up to 20amp,7amp continuos.

I have about 22 feet of cable with single ended encoders and servo
motors bundled loosely together from the CNC control to the machine.
I have had no problems at all. Now, the Servo-to-Go card that I'm
still using has the digital filtering of the encoder signals built into
the LS7166 chip. I don't know how much filtering (if any) Mariss
has in the Gecko drive. I also am not running a plasma torch with
this system. But, my VFD definitely noised up some other gear,
and until I put some filtering into the E-stop circuit, switching
motors off caused estops, but I never had any interference with
my encoder signals. I AM using shielded cables for the encoder
signals.

Jon