Commercial name for specific type of two-beam photoelectric alarm?

[gomipile]

What I'm looking for is an alert system that rings a bell/plays a sound/ whatever when the beams are broken in one direction. So, it'll have two beams with reflectors on the other end, installed side-by-side. If placed at an entryway, the receiver will sound if someone walks into the building, but not when they walk out.

I'm 90% sure I've seen something like this in the past, but I haven't been able to figure out the right Google or Amazon keywords to find any like this. So, if they exist as a product with a consistent description, I'd like to know what that description is.

[halfeye]

What I'm looking for is an alert system that rings a bell/plays a sound/ whatever when the beams are broken in one direction. So, it'll have two beams with reflectors on the other end, installed side-by-side. If placed at an entryway, the receiver will sound if someone walks into the building, but not when they walk out.

I'm 90% sure I've seen something like this in the past, but I haven't been able to figure out the right Google or Amazon keywords to find any like this. So, if they exist as a product with a consistent description, I'd like to know what that description is.

It sounds as if there would be at least one edge case where someone stopped in one beam and then someone else came past them in the other direction.

[gomipile]

It sounds as if there would be at least one edge case where someone stopped in one beam and then someone else came past them in the other direction.

True, but the use case is for a doorbell at a store. If it works correctly the vast majority of the time, that's good enough. It wouldn't be depended on for security.

It would be replacing an ordinary IR motion detector that already sometimes misses people tall enough to step over it, and triggers unexpectedly once in a while for no apparent reason.

Oh, and it would be used in a normal single width doorway, so that'd probably only happen with two children going opposite directions, which would be very unlikely where I'm thinking of this being used.

[Manga Shoggoth]

Would this be what you are after?

The wireless people counter features a continuous, invisible dual-beam across the doorway, it announces the entrance or exit of customers with a pleasant chime sound.

I presume it can be configured to disable the exit chime (or at least differentiate it from the entrance one).

[gomipile]

Would this be what you are after?



I presume it can be configured to disable the exit chime (or at least differentiate it from the entrance one).

Thanks. I'll see if that gives me anything. One security professional I talked to mentioned camera+computer based people counters as the only solution he was aware of, so I think you're on the right track. Or a right track, at any rate.