Help needed testing Ajax systems indoor motion sensors for possible weakness

bel12

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Hi all,
I have been testing my Ajax system for a while now, and I must start by saying these systems are top notch, so please don't take this post as anything against the maker, on the contrary - I find Ajax to be one of the best out there.

That said, while testing I did find some problems, one of which is the following, and is being denied by the company (which is very responsive and always replies):
They publish their indoor motion sensors as having "Pet immunity" for weight — up to 20 kg, and height — up to 50 cm. Naturally this would be great for domestic users who own a cat or small dog.

Unfortunately, testing a well installed motion sensor (both MotionCam & MotionProtect Plus) at 2.4m height and following all installation instructions down to the letter - will not detect an 80 kg guy going on 4, fast, around it's whole protection filed, be it far or close by, towards the sensor or across it's filed.

Following Ajax's advise, I have uploaded a video to their lab people to analyze, and the final conclusion was that they claim something is wrong with my installation, they just can't put their finger on what exactly, even tough they have asked and received follow up information and image materials to explain and show the area in detail.

I have repeated this test in other rooms with several other motion sensors, and unfortunately got same results.

I'd hereby like to kindly ask our fellow forum members to test their own Ajax indoor motion sensors while going on 4 and inform us of your findings, so that I could potentially better understand what I did wrong, or otherwise follow up with Ajax and ask them to consider a fix.

Thanks in advance!

P.s. - can you test another maker's sensor that claims to have such "Pet immunity"? Please do! Video demonstrations and technical insights about you installation are highly appreciated (height, is there floor heating there? etc.).
 
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sebastiantombs

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I'd have to agree with Ajax. The way motion detectors work, PIR motion sensors assumed here, they "look down" at an angle. If they're mounted just a little too high they won't detect. That height is critical and the angle is also dependent on the range of the device. I'd say it' mounted a little too high for the range it's working at, but that a "sight unseen guess".
 

bel12

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I'd have to agree with Ajax. The way motion detectors work, PIR motion sensors assumed here, they "look down" at an angle. If they're mounted just a little too high they won't detect. That height is critical and the angle is also dependent on the range of the device. I'd say it' mounted a little too high for the range it's working at, but that a "sight unseen guess".
Thanks, but I'm not sure I understood your take on this, as 2.4m is the exact installation height recommended by Ajax instructions.

My only point is - they should not claim something works in a specific way if it doesn't. In other words, if Ajax motion sensors can be overcome by simply going on 4, what is the point of having them? Are we really testing motion sensors only out of hope that all burglars are dumb enough to walk around normally?

I know very well that the system in it's entirety should and can cover other aspects, and therefore is not deemed useless. But hey - this is basic stuff expected from a motion sensor - I'm not even talking about crawling like a snake, just a man going on 4.
 

sebastiantombs

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It's a simple question of angles, nothing more, nothing less. The lens of the PIR has segments and each segment has a specific angle for left, right and down. Each room is different, different size, different proportions. Unless the down angles are correct for the particular installation things can go undetected. I'm guessing it detects someone walking erect in the room. That says that the detector is working. It could be a mis-aligned lens, but I would think that would be pretty obvious during QC inspection although it could have happened during shipment or installation. Have you had your installer check the detector internally to make sure that is not the case?
 

bel12

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It's a simple question of angles, nothing more, nothing less. The lens of the PIR has segments and each segment has a specific angle for left, right and down. Each room is different, different size, different proportions. Unless the down angles are correct for the particular installation things can go undetected. I'm guessing it detects someone walking erect in the room. That says that the detector is working. It could be a mis-aligned lens, but I would think that would be pretty obvious during QC inspection although it could have happened during shipment or installation. Have you had your installer check the detector internally to make sure that is not the case?
I must disagree, I think you complicate and excuse a simple situation. allow me to explain:
I claim that Ajax claim for pet immunity only "up to 20 kg, and height — up to 50 cm" is invalid, point. You can place their motion sensor in any empty space, 2.4m above the ground and go very fast on 4, you will not be picked up.
That said, obviously if you point the angle of the sensor down, or install it lower than the manual's guidance, it will detect you going on 4 - but you lost either claimed normal detection range or the real pet immunity accordingly.
Hence, I don't like the explanation of "well it's a complex world" if the test is done in an empty lab. And trust me - I tested it in so many places, empty and not, types of ground, angles etc.. The simple fact is - their motion detection is both pet proof and unfortunately also "burglar detection" proof when installed correctly, if your burglar is going on 4.
 

sebastiantombs

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Think what you like, complain what you like. I've been using PIR detectors since they came out and have lots of experience with them under conditions that you will never experience and made them work without falsing. Enjoy yourself. I gave you an honest evaluation, it's up to you to either apply it or ignore it.
 

bel12

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Think what you like, complain what you like. I've been using PIR detectors since they came out and have lots of experience with them under conditions that you will never experience and made them work without falsing. Enjoy yourself. I gave you an honest evaluation, it's up to you to either apply it or ignore it.
I do thank you, and value your replies! :)
 

tangent

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You can throw a heavy blanket on your back and crawl around without tripping PIR sensors too. I've always been fascinated by how things work. When I was a kid and were were visiting a relative with an alarm system I made a game of sorts of trying to move around without the PIR sensor detecting me. There are all sorts of conditions in which a PIR sensor may not detect you, especially a pet immune one.

If you've got a particularly high security application without pets, there are sensors that are more sensitive (not compatible with your alarm), but they all have their limitations.
 

k-8

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Hi I’m new here. I came across this site while searching for Ajax pet immunity settings.

I had an incident at my home where the Outdoor Motion cams did not pick up an intrusion. I decided to test all 5 of my Outdoor Motion cams by crawling on all fours and running past them at full speed. The detectors failed to pick up on both tests.

I must say I’m quite disappointed. I was and still am a big fan of the Ajax system but this has left me disenchanted. I’m now considering using a different brand of outdoor sensors with an Ajax transmitter.
 
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Hi I’m new here. I came across this site while searching for Ajax pet immunity settings.

I had an incident at my home where the Outdoor Motion cams did not pick up an intrusion. I decided to test all 5 of my Outdoor Motion cams by crawling on all fours and running past them at full speed. The detectors failed to pick up on both tests.

I must say I’m quite disappointed. I was and still am a big fan of the Ajax system but this has left me disenchanted. I’m now considering using a different brand of outdoor sensors with an Ajax transmitter.
Hello! We recommend that users contact only qualified installers and security companies for the correct installation and adjustment of the devices. Also, you may contact our Technical support for help.
You can contact them via:

Email – support@ajax.systems
Telegram –
Or call:

+38 (044) 538 13 10
+38 (066) 022 44 32
+38 (068) 597 36 07
 

bel12

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Hi I’m new here. I came across this site while searching for Ajax pet immunity settings.

I had an incident at my home where the Outdoor Motion cams did not pick up an intrusion. I decided to test all 5 of my Outdoor Motion cams by crawling on all fours and running past them at full speed. The detectors failed to pick up on both tests.

I must say I’m quite disappointed. I was and still am a big fan of the Ajax system but this has left me disenchanted. I’m now considering using a different brand of outdoor sensors with an Ajax transmitter.
Well, don't be too much disappointed, the important thing is that you improve going forwards, and do your best to prevent intrusion from reoccurring.

I wonder, did you install it DYI?
Was that the only/last line of defence?

It is important to note, that since this post, I have tested some (indoors) PIR sensors with and without pet immunity, I have to say - mostly they don't pick up on low crawling. Haven't seen the Ajax 'MotionCam Outdoor' yet, but from the manual, it seems like it is really just a sensor to know if the postman came by, not more. That said - if an intruder saw it and decided to pass it, I find that weird, since it might/should indicate that you have some hi-tech stuff to protect the peremesis. Maybe this person knew what you had & where beforehand.

Generally, burglary is a bit more complicated than just defeating the alarm, and even if we do focus on the alarm weaknesses out there - almost every sensor has a weakness which can (& will) be exploited, whether it will be by swapping magnets on door contacts, masking PIR sensors etc. etc..

I highly recommend watching this guy speak, he gives people a great peek into the mindset of some of the burglars, and also makes it clear how much good neighbours play a role, deterring many from even considering a street/neighbourhood.

I agree with Ajax that a good installer is crucial when one is new to the art (I think it's an art), but there is no substitute to your extra steps!

Good luck.
 
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