Is there a standard protocol for motion sensors, PIR sensors, etc. to tell parking lot lights, etc. that motion has been detected, so the lights need to turn on?

I'm not asking for protocols that could be used. Hundreds of protocols could be used for these systems, such as "+12 V for motion, GND for no motion", "X10", "+5V for no motion, GND for motion", "Zigbee", or etc.

What signal levels and number of wires, etc. are actually used with off-the-shelf sensors? (An ideal answer will link to one or more datasheets for such sensors).

(This question was split off from How do you dim a streetlight bulb? ).


While I appreciate the datasheet for the "actual sensor" PIR component, I'm not so much looking for the voltages/timing on the pins between the "actual sensor" and the PCB it is soldered to. I'm looking more for: What is the the voltages/timing on the long wires/cables running between the off-the-shelf prepackaged "sensor assembly" (is there a better term?) and the lights? How else can I design something to be compatible with many off-the-shelf devices, some of which haven't even been designed yet, rather than only working with one particular device?

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    \$\begingroup\$ I think that the simplest thing is to choose a sensor and look at the datasheet; it's not sure that there is a standard for such systems. But since these sensors are used in simple circuits, probably they just give a high signals (i don't know the exact level) that allows to close a relay; or probably, many of them has already the relay inside, so they just close a contact when presence is detected. \$\endgroup\$ – clabacchio Jan 15 '12 at 18:07
  • \$\begingroup\$ What I've seen is that there are wired sensors as wireless sensors, there are some for PCB mounting, and some for wall mounting, ready for connecting to the supply: which one do you want to interface to? \$\endgroup\$ – clabacchio Feb 3 '12 at 20:10
  • \$\begingroup\$ @clabacchio: I want to interface to wall mounted ready-to-go sensor boxes. \$\endgroup\$ – davidcary Jul 18 '12 at 16:01

Normally the actual sensor consists just of one or two photodiodes (two if it is a differential sensor) sensitive for thermal IR radiation and most of the time a FET transistor integrated in one casing.

So there is not much "protocol".

Take a look at this example datasheet

Of course you can buy also more complex sensor circuits that implement whatever protocol.

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