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Arduino Input isolation

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Iceman
(@iceman)
Active Member
Joined: 1 year ago
Posts: 7
Topic starter  

Does anyone know of an input isolation shield for the Arduino UNO? I think I might need some sort of opto isolation for the inputs as they will be running from read switches  that are 50 to 100 ft. away. The wires being that long will pick up RFI of some sort. This is only a residential setting but still there is RFI all around us. I know I could use optocouplers and build a circuit but it would have to be separate from the Arduino UNO and then wire to it. Not a big problem, but if a shield was available it would be more compact.


   
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DaveE
(@davee)
Noble Member
Joined: 2 years ago
Posts: 798
 

Hi @iceman,

  I suspect with reed switches, you will need some 'debounce' provision, be it RC filter and possibly software that samples several times before acting on a change of state. In addition, diodes to limit excursion could be needed/advisable .

A quick Google showed a discussion similar to my above comment from Digikey that you might find helpful https://www.digikey.co.uk/en/articles/protecting-inputs-in-digital-electronics

However, I would stay with the twisted pair long wires, Not rely on Earth return wiring as the article discusses.

Elsewhere BAT54 was suggested for a Schottky diode type, though you may need to look for similar substitutes.

.. I am sure there will be many other discusions on the web

Hope it helps ... sorry it is not shield... maybe others can help.

Best wishes, Dave

 

 


   
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Iceman
(@iceman)
Active Member
Joined: 1 year ago
Posts: 7
Topic starter  

Hi @davee 

Thank you. I will look at that option.

 


   
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