Hey there people, I have just completed building a DSI lighting ballast controller, part of the controller involves triggering from an external source such as a motion detector, momentary switch- whatever (240v or 5v). (triggers a ATMEGA8 interrupt)
Currently I want to use a PIR motion detector as its trigger, however I am running into problems deciding on what PIR to use.
The PIR is to be situated in a pathway that is 2.1m wide, so it only needs to detect over a narrow distance, however the acceptance angle in Plan view needs to be fairly wide.
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Ideally I want to use a PIR detector that is small, and perhaps can even be mounted in a weatherproof/vandalproof vessel of some sort (if it doesn't already fulfill this prerequisite).
Most of the security based PIRs are too large and have too big a detection area for my needs.
The detector is to be used in a commercial installation on a boardwalk overlooking the ocean - so it needs to be fairly sturdy and reliable.
Any ideas would be greatly appreciated.