Direct Output module pins protection

[rodrigo_rt]

Hello!

I'm trying to power a relay using one of the pins for the DO Module of my Revolution PI. I also need to have a way to power the same relay using a manual button. Here's a simplified diagram of what I'm trying to do:

RevPI DO in.png (5.88 KiB) Viewed 9736 times

My question is: Does the DO Module have any built-in protections so the current from the button being pressed doesn't go inside the pin? Or do I need to do place a diode like this to avoid the current going in?

RevPI DO in with diode.png (6.08 KiB) Viewed 9736 times

Thank you for your help!

- Rodrigo