Dynomotion

Group: DynoMotion Message: 9297 From: rjreese29@ymail.com Date: 3/4/2014
Subject: Gnd standoff hole
Hi, Just getting to mounting and wiring up. What is best practice with the GND standoff on the board? Mount a standoff on this and star-ground near it, or don't mount it? Whats the overall best experience with this? I have a metal enclosure and preventing any power supplies in this enclosure. Thanks Rob
Group: DynoMotion Message: 9298 From: Tom Kerekes Date: 3/4/2014
Subject: Re: Gnd standoff hole
Hi Rob,

Grounding is very complex and every situation is different, but normally I think it would be a bad idea to use a stand off on the KFLOP GND Lug to connect KFLOP GND to the frame (Earth GND).  The frame of the machine can be very noisy and may even have voltage spikes large enough to damage KFLOP.  This may also form ground loop where Earth GND currents that would be expected to flow through the frame to Earth now follow a alternate path into KFLOP through the USB Cable, through the PC, then to Earth GND.

The KFLOP GND Lug can be useful for multiple DC GNDs going to relatively quiet/clean devices like encoders, step/dir drives, MPGs, etc...

HTH
Regards
TK 

Group: DynoMotion Message: 9299 From: Rjreese29 Date: 3/4/2014
Subject: Re: Gnd standoff hole
Thanks so much Tom!!!

Rob

On Mar 4, 2014, at 8:41 AM, Tom Kerekes <tk@...> wrote:

 

Hi Rob,

Grounding is very complex and every situation is different, but normally I think it would be a bad idea to use a stand off on the KFLOP GND Lug to connect KFLOP GND to the frame (Earth GND).  The frame of the machine can be very noisy and may even have voltage spikes large enough to damage KFLOP.  This may also form ground loop where Earth GND currents that would be expected to flow through the frame to Earth now follow a alternate path into KFLOP through the USB Cable, through the PC, then to Earth GND.

The KFLOP GND Lug can be useful for multiple DC GNDs going to relatively quiet/clean devices like encoders, step/dir drives, MPGs, etc...

HTH
Regards
TK