I keep having the need for dry contact interfaces.  I need it both ways.  I need a device that when it sees a dry contact closure it can activate TP Link devices (lights, etc).   I also need one that, when it sees a signal, will give a dry closure.  This would open up so many possibilities for interfacing and custom home automation.  For instance, an existing alarm or driveway sensor, could turn on TP Link controlled lights.  It should be simple.  You already have a contact and motion detector that will do this.  (X-10 had an Alarm Interface module that did this 40 years ago, so I know you can do it today).  The other one would be great if you wanted to use the TP Link system to control anything else (via dry contact output).