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Interference
« on: May 28, 2012, 01:26:15 PM »
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Has any had interference activating their Pokeys device?  What cured it?
 
I am getting interference, activating inputs to my Pokeys55 device.  This is pretty serious with one event  Z axis moved towards table without any input from me. Luckly we were able to hit the e stop before damage.

We have fitted many buttons connected to pokeys to do functions such as auto tool zero, open Mach3, home. etc

We suspect a new power supply used to power  new Gecko 540 drive.  We are not suspecting the latter as we have had events while no drives were being driven.
 
Actions we are considering (before reactivating this) are to add a ferrite to the PSU mains cable, and add 0.1uf capacitors to all the input switches.
 
Comments/suggestions and if possible experience much appreciated.
 
John.

Offline Hood

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Re: Interference
« Reply #1 on: May 28, 2012, 04:55:29 PM »
With 5v signalling you really need properly shielded wiring on everything so if you have not got that already it may be worth doing.
Hood
Re: Interference
« Reply #2 on: May 30, 2012, 01:00:34 PM »
Many thanks Hood.
 I have found some suitable sheilded wire from Farnells and will replace all original wires to Pokeys . I will also add capacitors to be on the safe side.

John.

Offline borisz

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Re: Interference
« Reply #3 on: May 31, 2012, 07:23:34 PM »
Also pull up about 1k and 100n cap paralel to switch may help you.
www.poscope.com home of PoKeys USB HID, IO, USB, Ethernet controler and PoScope USB PC oscilloscope
Re: Interference
« Reply #4 on: June 01, 2012, 03:41:05 PM »
Many thanks for that. Do you think there is any advantage in shielding pokeys board with metal casing also.

Offline borisz

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Re: Interference
« Reply #5 on: June 01, 2012, 04:43:22 PM »
Hi!

Please first check with pull up and cap. Maybe adding shielding cables could add aditional protection, but my opinion is that cap and pull up should be enough.
Aditional shilding may help if upper measure will not bring satisfactory results.
www.poscope.com home of PoKeys USB HID, IO, USB, Ethernet controler and PoScope USB PC oscilloscope