Can a PIR be set off with a laser beam?

[BarbaraW]

We have an ongoing issue with the guy on the motorcycle that delivers The Star newspaper in the early mornings in our area and need some advice.

He triggers our external beams setting off the alarm almost every morning between 03:45 and 5:15 (the exceptions being the mornings that the ADT car is parked nearby). This has been going on for several weeks now. We live on the corner - one of the roads comes to a dead end about 100m past us, and the other is a panhandle. To trigger the alarm he has to drive into the panhandle. We know for a fact he has no need to do this as there are no longer any subscribers here (one of our neighbours cancelled his subscription 3 weeks ago). So he is deliberately driving into the panhandle to trigger our alarm - we have absolutely no idea why.

We have had the angle of the beams that cover the gate on this side changed 3 times and the PIR moved to a different location and he still manages to set it off. Neither the security company that installed the alarm system nor the ADT technician can figure out why. We have tested extensively and it is impossible to trigger the alarm from outside the gate (well recessed off the road) whether on foot, on a bike or in a car. So from what we can make out, he must be using a laser beam - from Google research we've done it appears this is possible although neither technician had heard of this before. So our questions are:

- Has anyone else had a similar problem? If so, have you been able to address it and how?
- Does anyone know of a security company that has experience of this kind of thing, and can review our security system and help resolve the issue? (We are in Morningside Manor, Jhb)

Any suggestions would be very welcome... thanks!

 

[airborne]

Why would the paper delivery guy want to trigger your beams?

 

[HunterNW]

How do you know he is deliberately doing this just to set off your alarm ? And going all the way to get a lazer to do it ? Something is fishy.....
Do you owe him money ? Did you have sex with him ? Do you have a daughter ?

 

[BarbaraW]

Why would the paper delivery guy want to trigger your beams?

We ask ourselves the same question every time it happens.

 

[BarbaraW]

How do you know he is deliberately doing this just to set off your alarm ? And going all the way to get a lazer to do it ? Something is fishy.....
Do you owe him money ? Did you have sex with him ? Do you have a daughter ?

Because he has no deliveries to do in our part of the road, only much further up. Yes, very fishy and no to all the rest.

 

[Geoff.D]

PIR's are triggered by a change in IR radiation. That change can be from many sources these days. Sunlight is well known, but new LED lights used by many of us also trigger the PIR. ( on car and bike headlights for example). It could be completely unintentional on his part.

The only way is to shield the PIR against it with a shield of some sort so that all it is exposed to is the single beam of the transmitter.

This means a far better and more accurate installation of both receivers and transmitters.

North-South gates, the PIR is installed on the northern side as an example so that sunlight shining onto the PIR is limited. Movement sensors and day/night sensors need to be shielded from direct light sources as well.

We had the problem with a neighbours installation where his movement sensors were so aligned that our gate lights would trigger his alarm system. The only solution was for him to reposition his movement sensors to remove any line-of-sight situations with our lights as the moment we switched on our outside lights, his alarms would go off.

 

[HunterNW]

Because he has no deliveries to do in our part of the road, only much further up. Yes, very fishy and no to all the rest.

What make and type is the outdoor beam ? Or is it a PIR ? Beams are 2 units looking at each other.

 

[D tj]

A few early morning diesel spillages on a section of road before your driveway ought to bring an end to the riders inquisitiveness.
Diesel at the start of the panhandle....easy application.

 

[BarbaraW]

What make and type is the outdoor beam ? Or is it a PIR ? Beams are 2 units looking at each other.

It's a PIR

 

[BarbaraW]

PIR's are triggered by a change in IR radiation. That change can be from many sources these days. Sunlight is well known, but new LED lights used by many of us also trigger the PIR. ( on car and bike headlights for example). It could be completely unintentional on his part.

The only way is to shield the PIR against it with a shield of some sort so that all it is exposed to is the single beam of the transmitter.

This means a far better and more accurate installation of both receivers and transmitters.

North-South gates, the PIR is installed on the northern side as an example so that sunlight shining onto the PIR is limited. Movement sensors and day/night sensors need to be shielded from direct light sources as well.

We had the problem with a neighbours installation where his movement sensors were so aligned that our gate lights would trigger his alarm system. The only solution was for him to reposition his movement sensors to remove any line-of-sight situations with our lights as the moment we switched on our outside lights, his alarms would go off.

This is helpful, thank you!

 

[Pandarye]

Are you absolutely certain that it is the delivery driver causing the problem? e.g. Have you watched him approach your property and see at exactly what point the alarm is triggered?

I recall my father having endless issues with this outdoor beams being triggered at certain times. One of the suggestions for the problem included reflections from the sun at a particular time of the morning.

 

[BarbaraW]

Are you absolutely certain that it is the delivery driver causing the problem? e.g. Have you watched him approach your property and see at exactly what point the alarm is triggered?

I recall my father having endless issues with this outdoor beams being triggered at certain times. One of the suggestions for the problem included reflections from the sun at a particular time of the morning.

Yes, absolutely certain it is the delivery driver. We hear the bike approaching and then our alarm goes off and the bike departs - the same sequence every single time. The sun isn't up yet this early, between 3:45 and 5:15 am.

 

[D tj]

It may be worth stopping the rider and having a polite chat, as they are in all likelihood wearing a helmet and are oblivious to the nuisance they are causing....1x chat could be all needed to solve it.
Otherwise pole or...... diesel...last resort.

What about a cheap single pole /2 pole gate across the panhandle closed at night till perhaps 6 am?

 

[BarbaraW]

It may be worth stopping the rider and having a polite chat, as they are in all likelihood wearing a helmet and are oblivious to the nuisance they are causing....1x chat could be all needed to solve it.
Otherwise pole or...... diesel...last resort.

What about a cheap single pole /2 pole gate across the panhandle closed at night till perhaps 6 am?

The ADT car in the area has stopped him and had the chat, so he is aware. When the ADT car is around, he turns much further up the road and doesn't come down our end at all. When the car is not around he sets the alarm off, every time!

It could be worth investigating the pole gate - will need to check with the other households up the panhandle if they'd be ok with this.

 

[Sinbad]

It's also possible that the hot exhaust and engine on the bike set off your PIR from a lot further away than a normal human being would do, as these work by detecting movement of heat sources.

 

[BarbaraW]

It's also possible that the hot exhaust and engine on the bike set off your PIR from a lot further away than a normal human being would do, as these work by detecting movement of heat sources.

We've checked that out - the gate is recessed about 20m from the road and the PIR is another 15m from the gate, so there is a fair distance. We've experimented with cars and bikes in all temperatures of weather and not been able to set it off ourselves.

Also, there is no reason at all for this guy to be in the road.

 

[D tj]

Ok, a simple remedy: he is being difficult then....ADT chat.

2.4m x 22 mm x70 mm SA pine plank, paint it matt black, then drill lots of 3 mm holes about 20 mm apart...basically x3 rows down the length of the plank, take size 8 x 35 Pozi drive chipboard screws (360 screws ) and screw into holes...flush or slightly countersink screws...spray protruding screws matt black....place across the road. if this is on a black rope it can be pulled back if a car comes or as he goes over it.

The other is rocks or brick pieces again sprayed or painted matt black, scattered +- 1m wide area across road.
The matt black...ought to be invisible in poor light.....

 

[HunterNW]

CCTV and Sublethal Remote Guns

Upgrade your CCTV to have a remote gun on site. Don't just watch criminals take your belonging, shoot them! A remote gun is better than having a 24 hour security guard.

www.sublethal.co.za

Have fun getting rid of the guy.

 

[Geoff.D]

It may be worth stopping the rider and having a polite chat, as they are in all likelihood wearing a helmet and are oblivious to the nuisance they are causing....1x chat could be all needed to solve it.
Otherwise pole or...... diesel...last resort.

What about a cheap single pole /2 pole gate across the panhandle closed at night till perhaps 6 am?

Cause it may be illegal and costly.

 

[grok]

This sounds like a problem a once-off early morning vigil with a baseball bat could sort our in a jiffy..