Preventing Shorts When Using Arduino Ethernet Shield
I discovered this a while ago but I thought it would be important to share in case anyone is working on a project using an Arduino Ethernet shield. Most shields connect directly to the arduino board using the standard cascading pin system. The Ethernet shield like many others has the cascading pin feature but what it does not account for is the fact that the Ethernet jack on the board stands higher than the rest of the female pins. I have tried attaching boards above the Ethernet shield and the bottom of the board ends up contacting the metal on the top of the jack. This results in a short circuit if the problem is not noticed before the boards are powered up.
As a quick and easy solution all you have to do to prevent this is place a piece of tape or insulated adhesive over the metal Ethernet jack. This prevents shorts even if another board is directly contacting the jack.