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I'm still not sure as to why all the churchs buildings need to be surrounded by photoelectirc sensors.

I think those are IR motion detectors.
They way they are placed if I see that photo correctly is that anyone walking towards the building would set it off. (photo 18)

Atheist

infared beam goes from one to another,something breaks the beam and it sounds an alert in the sec. office....then they refer to the appropiate camera for a quick look at the intruder before calling in the heavy artillery.....what a job for a minister..i mean preist..i mean sec. agent.... ....whoops wrong photo,sorry..thats a 360 deg. video cam...under a bulb...

That's just... creepy



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They are photolectric.... its just a fancy name for overpriced motion detector

That is freaking scary! Why would a church need so much security???

It seems like they don't want anybody coming in, or coming out. In my book that is far from being a church.

What do they have to hide ????????

EXACTLY....

There's more of a difference than that.

Photoelectric strictly speaking is a modulated (usually infrared) beam between a transmitter and receiver (or can be reflected, with both T & R in one housing). When something passes through the narrow beam breaking it, there's an alert signal. Alignment is fairly critical with this type, but they work well as long as there isn't too much ambient light interfering with the beam(best indoors). Not really a motion detector in the true sense.




These units look like passive infrared (PIR) motion detectors, which don't produce a beam but monitor for changes in IR radiation over a wider area, like when a warm body or vehicle enters/passes. I see 2 mounted to this stake, at right angles to each other.




This is a pan/tilt/zoom patrol camera which can be operated remotely and/or set to continuously scan a programmed path. Pretty sophisticated stuff. They cost $1500-2000 apiece. The hot setup is to hook these up to a controller triggered by PIR or beam sensors directing them to follow and record detected motion events.




I don't know what this smaller device is. Possibly a fixed camera to continuously cover a specific area while the larger PTZ dome is free to scan a 270 degr area on both sides of the corner, or maybe its an IR spot illuminator.





The box like things are weatherproof camera housings. Sometimes they're mounted on pan/tilt platforms, but these appear to be fixed.

They are not passive infrared (commonly called pyroinfrared). They ARE photoelectric (which is IR)as you described above. They look like they may be made by Optex.I know that in technical terms they are not "motion sensors" but beam sensors. But in generic terminology thats what they are called.

The Yachtsman features sensors on all the walls, to make sure no one leaves at night. When any sensor beam is broken, a chime goes off in the reception.

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