Connection detect for 120VAC plug?

I'm designing a new product and we need to know when someone plugs a cord into our NEMA 5-15 socket (a standard American 120VAC receptacle).

If this were a an audio plug or a barrel jack I could just use the insertion detect terminal - but I can't find any AC plugs that have that kind of a switch in them. Does anyone make such a plug?

Currently, I'm thinking of pointing a beam break sensor across the face of the plug so I can just see that *something* is there, but I'm not thrilled with this solution.

Thanks!

Depending on current, you might be able to detect the voltage drop across a pair of back-to-back diodes in series with the load.

It seems that in the distant past I saw outlets that had a small button protruding from the center of the face. When the plug was inserted it pushed in the button and closed an internal set of isolated contacts. You might try calling or emailing one of the major outlet manufacturers: Cooper, Pass-Seymour, and Hubbell.

Ken

Wade - Unforunately, there won't be any voltage on the line when I need to detect a plug-in event. We'll be switching the power on some time after the plug is connected. (sorry I can't give details on exactly what we're doing... I'm not sure what I'm allowed to divulge)

KMoffett - thanks for the manufacturer names. I'll go check out their sites.

Amazon.com: Hubbell 5942-6 Do it Weatherproof Electrical Cover:…

You could use one of those with a switch to detect that the lid is or isn't closed.