Looking for simple input status shield or proto circuit

I am looking to count pulses from a dry contact. So, I will need whetting voltage and a place to land the wires from the dry contact. Is there a shield for this or has someone already created a proto project that does this?

Hi,

https://www.arduino.cc/reference/en/language/variables/constants/constants/

Look up this link and goto INPUT_PULLUP .

This may solve your problem.

Tom.. :slight_smile:

This definitely helps with the code but, not the hardware. I'm assuming I'll need some type of opto-isolation to protect my Uno.

Any other suggestions?

Hi,
Dry contact means its isolated, just a switch output?
What is the device, can you post a link to manual or spec/data sheet?

Thanks.. Tom.. :slight_smile:

No need to post a link, it is a simple dry contact that has to be whetted. Does the Uno provide a whetting voltage with enough current for a 30 foot cable of 22 ga wire?

Bugman1400:
No need to post a link, it is a simple dry contact that has to be whetted. Does the Uno provide a whetting voltage with enough current for a 30 foot cable of 22 ga wire?

You may have to use an external pullup resistor to provide your “wetting” current, if you are switching to gnd.
Or an external pulldown if you re switching 5V supply.
6vbduK2.jpg.png
Tom… :slight_smile:

Thank you! This schematic was a big help!