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Motion Sensor and Cats

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umery2k75

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alarm sensors with cats

Hi,
I bought couple of motion sensors long ago. I installed one at the entrance space of home. I have 2 cats at home. Yesterday night I turned those motion sensors on to detect intrusion.Problem is that my cats lives outside the rooms, they move from roof to downstairs and even go outside the home and come back.Even other cats come to my cats place to eat their cat food. My sensor detects the cat as intrusion and turned on the siren at full volume at night, disturbing us and our neighbours. I was thinking if there's solution to this problem that I can do with it, because I can't control the Cats, even if I keep my cats inside the home in rooms, then other cats have developed the bad habit of coming to my home to eat cat food, they never use to come before, they now start visiting my home when they see I put cat food in home, easily accesible to them, so few other cats visits my home. I first observed how the sensor works. It has a one red LED in the sensor, If I'm not wrong they are infra red sensors, I'll double check it when I reach home.Whenever the sensor detects something, the LED gets on and simulatenously the siren gets on. LED lits for 2-3 sec and then it turns off. Suppose if I walk in it's path. The motion detector will detect me and lit it LED along with siren. If I remain still over there and don't move a muscle. It gets off. If I move a little bit from that position it detect me again. I was thinking that I should make an electronic circuit that would count how many times a motion detector detects an object in specified time period, then triggers it up. If somebody is moving in it's path,and if detector sensed it 2-3 times within 5 sec, it triggers on the alaram. If cat walks within that area, the sensor detects it just around 1-2 times within 5 sec and not more than that. So, I think that a counter would be use, which counts the number of registered intrusion within a time. At around 5 sec, the timer would reset the counter. If counter reach value of 2-3, then it triggers on the alarm. It means a lot of movement is done in the resctricted alert area, that much movement is not done with cats.Please share your view on it.
 

pet immune motion detector for cats

The sensors that I am familar with are PIR sensors. They are IR sensors that detect movement or changes to the IR field of view. The signal output is analog and the detection is determined by analog filters and time delays.
There are several sensors on the market that are "pet immune". Please see the link below. They are probably very similar to the ones you own with some different resistors and capacitors to change the tuning of the filters. The problem is knowing which Rs and Cs to change. The danger is tuning it too much and missing a real intruder. (You can try your own search for "motion sensor pet immune" also.)

https://www.homesecuritystore.com/ezStore123/DTProductList.asp?p=2_1_1_1_0_0_194
 

alarm motion sensor cats

As the PIR (pyroelectric infrared) sensors are detecting thermal radition differences of objects, they are particular sensitive to warm-blooded animals. I doubt, if a pet immune construction can be reliable enough to operate an outdoor burglar alarm, but you can give it a try. With professional alarm systems, it is only used indoor, I think.
 

infrared sensors cats

The model that I have with me is DS940, it's written Passive Infrared Motion Detector.
I found it in this web **broken link removed**.

Added after 14 minutes:

On its manual, it's written as:
Description
The DS940 is a high performance Passive Infrared (PIR) Motion Sensor which uses advanced signal processing to provide outstanding catch performance and unsurpassed false alarm immunity. It is designed to detect movement in the interior of a structure by sensing the infrared energy emitted from the human body as it moves across the sensor's field of view. When motion is detected the unit sends an alarm signal to the Control Panel.

Avoid
Direct Hot or Cold Drafts -> Oven was made in the manual
Air Conditioning Outlets -> AC was made in the manual
Windows and Uninsulated Walls -> Wall window was made
Direct Sunlight -> Picture of Shinning sun
Mounting Outdoors -> Picture of Home taken from Outside
Heat sources -> Stove
Moving Objects ->Ceiling fan
Pets -> A dog

It seems like the sensor is sensitive in design, next time I visit the market, I'll see if I could find sensors which are pet immune and other thing is that I have bought many of them, if I would have bought a single or two piece, replacing them wouldn't be costlier to me. If replacing them sounds costlier, then I will make a counter circuit, that will counts the number of detection, this would solve my problem.I have seen when pets wanders around the area, it generates less number of pulses to alarm, when a person moves in the area, it generates greater amount of pulses to alarm in the same area, because person is large and pet is small.

Added after 7 minutes:

Datasheet
http://www.boschsecurity.us/pdf/EN/40554J DS940-DS940T PIR Detectors Datasheet.pdf

Manual
http://www.boschsecurity.us/pdf/EN/38827H DS940_DS940T Installation Instructions.pdf

Technical Service Notes
http://www.boschsecurity.us/pdf/EN/42298D DS940-DS940T A&E Specifications.pdf
 

dc motion sensor cats

Well, as per the sensor installation guide:
http://www.boschsecurity.com.mx/_ar...mentos/intrusion/EN/ds940_install_0109_en.pdf

And considering U have not purchase the correct sensor, U can try 2 things .

1) Have U powered up the sensor and waited at least two minutes before moving in the detection area?

2) You can mask the sensor lens ( as per the sensor installation guide ) in such a way you create a corridor where the sensor gets blind.

Hope U solve the problem.

Best regards
 

motion detector to detect cats

While I wish you the best of luck with your counter idea, I don't think it will work based on the sensors I am familar with. Take a look at:

https://www.edcheung.com/automa/ms14a.htm

This is an X-10 device that uses PIR sensor. On these PIR sensors with an odd white bubble lense that looks like a bug eye, the actual magic is in the lense. The lense is designed to fragment the image and bounce different parts of it to different areas of the sensor. This is what allows the motion to be detected. Notice from the example schematic, that the entire detection circuit is a single dual stage op-amp with some RC filters. I do not own the pet immune version, but my guess is that it has a much more extensive analog section. Notice that the PIR sensor feeds only the analog op-amp and is AC coupled. The microcontroller is only monitoring the second stage op-amp which is a level detector.

Again, that is only my opinion and understanding of this particular example. Perhaps your devices differ and your counter idea may have merit. Trace your circuit based on the example and see that the output of the sensor looks like on a scope.
 

@omore
I do wait for 2-3 minutes or even more, before testing this one up.
@banjo
I'll trace up the circuit and will share it most likely today. I think my device would be much simpler than this one, because it doesn't have RF transmitter, but it do have a pushbutton, and this device is not battery powered, it needs a seperate DC power source.
 

Could U tell us what alarm panel are U using. Some panel allows to create a time window in such a way that the sensor must triger the zone more than one time into the time-window to recognize it as an alarm.

Also, another feature is to use cross-zoning. This feature allows to generate an alarm when the so programmed zones trigger.

A question. Are U also trying to use the sensor outdoor ? I make this question cos I saw a comment abt this.

Best regards and good luck !!!
 

I'm not using any alarm panel, it's just a relay with 12V siren. The unit is not in the sense outdoor. It's inside the home, but outside the room. It some what like this as shown in figure.

 

I see. Well, if after initializing the sensor as per the installation instructions the sensor continues detecting the cat, try to mask some detection zones in the lens.

PETs are a problem and there are sensors which analyze how they move for differentiating from humans. Although U mask the lens, consider if the cat jumps over the furniture.

Basically, the sensor has a IR detector whose output signal is proportional to temperature. Normally, room temp is lower that human body. When an objet at higher temp tham ambient ( also a hot air mass ) is exposed to the sensor, it gives a higher output level. The lens ( Fresnel ) makes some zones visible an others blind. There is also a counter, so if an objet moves crossing those areas, the pir element will generate pulses. Some sensor allows to adjust the pulse counter ( not yours ). Unfortunately guess I´m not bringing too much help.
Let us know if U are able to solve the problem.
 

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