A "touch switch" could be included along with whatever other sensing method
you choose. The advantage with this would be to actually disable the
systems' data collection BEFORE the lid is opened. I'm not sure how
critical your demands are -- just a thought.
--
Greg

Tim McDonough wrote:
>I'm working on an application where the sensor and electronics is
>mounted in the lid of a container. I want to sense when the lid of the
>container is off or open so that the device can ignore readings during
>this time period. Cost of the sensor/switch is an issue.
>
>My first thought was a mercury type switch like those found in wall
>thermostats. Any idea who makes these?
>
>Other options are a reed switch and magnet but the mechanics of making
>sure it always aligns properly could be expensive.
>
>Another option is a photo sensor since the inside of the container
>would always be dark when the lid is closed. Possible problems could
>be dirt blocking the sensor.
>
>I'm open to other suggestions as well.
>
>Tim

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