Are motion sensors THAT important?

mrshanes

Member
I'm in the planning stages of my pre-wire and I'm stumped on what to do with motion sensors. I have two dogs (both weigh around 70-80 lbs each). However, they are getting old and obviously won't be around forever. With the walls open, I can certainly prewire for the sensors now and just not use them. I've considered putting one in each room :) to use for some automation stuff with lights and other things with ELK M1 (I'm sure the dogs would love walking through the house with the lights coming on for them!). But, I would also use them for security (is that even possible to use them for both?). I will be doing contact sensors on all window and doors (main and lower levels at least) and some glass breaks throughout. So, should I go for motion or not? If so, any suggestions?
Thanks,
Shane
 
Definitely wire for them. They are an important layer in a security system. What if a person cuts a hole in the glass and doesn't actually open the frame? The sensor and glass breaks won't detect that. I realize it may not seem very likely, but no single part of a security system is unbeatable. A good security system is one that has the most working layers of security IMHO.

You can use the standard motion detectors for automation rules if you want. They report movement regardless always. It is the armed status that determines how the panel reacts to that movement. So a motion will always close that zone on movement, regardless of the alarm status.

The downside to using security related motion detectors is the fact that they are "desensitized" to prevent false alarms. Using a true occupation sensor for automation use is generally better becuase it will provide much more accurate detection. But you can't use it for alarm purposes because it would false on occation. Turning on a light for 5 minutes when the HVAC blows a curtain isn't bad, but setting your alarm off because of that isn't good.

So you either have to double up and use a PIR as well as a occupancy detector, or just use a PIR and have a light turned off on you occational because you were sitting still (reading a book, watching TV, etc). That is the real decision to make.
 
So, should I go for motion or not? If so, any suggestions?
Motion sensors are considered by burglar alarm professionals as an additional layer of protection which is only a backup to the primary layer of protection. The primary layer is called perimeter protection. Perimeter protection are the door and window contacts. Glass break detectors are included in this.

So if you have very good perimeter protection, this lessens the need for the motion detector. I have many customers who do not want motion detectors. There are plenty of reasons not to have them, and the main one is because of the high false alarm rate compared to the other sensors. Another reason is that PIRs can be defeated, by very simple means if you know the trick.

I would say if you have all doors and windows with contacts, and in addition, have glass break detectors, there are so few ways a burglar can gain undetected entry, that the PIRs can be eliminated.

What I have done for those customers who do not want them is to go ahead and mount the PIR, power it up but do not wire the contact. Leave it spare for future use. This has the added benefit of making potential burglars think you have them in the system.
 
About 18 years ago, I knew some pretty shady people. These guys were not very intelligent, and they got the idea to burglarize a gun store at 2am. As dumb as they were, they realized the place had a security system, and noticed during business hours that there were no motion sensors. So, they got a sawzall and cut through the back wall of the building in the alley and cleaned out the store. They took over 300 guns.

The crime went unsolved for about 2 years until one of them tried selling them to an FBI informant.

Bottom line is, these guys were not that intelligent, but were able to figure out if they cut through a wall with a sawzall that they wouldn't set off the alarm.

Put in motion sensors.
 
.... So, they got a sawzall and cut through the back wall of the building in the alley and cleaned out the store.

That isn't a new or even uncommon trick ether. Chain saws are also sometimes used in broad daylight for homes... as daytime lawn (service) mowers, trimmers, and blowers are normal neighborhood sounds.

Some people live and work full time by taking other peoples stuff. The best burglars aren't the "Robert Wagner TV type smart guys". The burglars that can most easily see your homes weaknesses, and then most quickly exploit them.. generally have a history of contruction work... and prison time.

If your using your home as your vault for your collections. And your collections have become valuable and/or easy to resell... your home is at risk. That is the good news. The bad news: There is nothing you can do to stop these people.

Wire for everything while the studs are exposed. Design your alarm system, based on what your trying to protect.
 
Can anyone recommend decent pet immune wired and wireless occupancy sensors? I have been wrestling with this for a few years now and it just clicked. I've been trying to use security motion sensors for home automation, and they are just too slow and unresponsive. And if you are relative still in a room, they will fail to realize that you are still in the room. So, thanks for reminding me of that.

Slight threadjack possibly, and if it detracts from the thread too much, I will start a new one.

So you either have to double up and use a PIR as well as a occupancy detector, or just use a PIR and have a light turned off on you occational because you were sitting still (reading a book, watching TV, etc). That is the real decision to make.
 
Can anyone recommend decent pet immune wired and wireless occupancy sensors? I have been wrestling with this for a few years now and it just clicked. I've been trying to use security motion sensors for home automation, and they are just too slow and unresponsive. And if you are relative still in a room, they will fail to realize that you are still in the room. So, thanks for reminding me of that.

Slight threadjack possibly, and if it detracts from the thread too much, I will start a new one.

So you either have to double up and use a PIR as well as a occupancy detector, or just use a PIR and have a light turned off on you occational because you were sitting still (reading a book, watching TV, etc). That is the real decision to make.

There is actually another solution if you look. A typical IR motion detector uses "fingers" to detect motions. These fingers are the detection areas of the motion detector. Imagine the motion detector is like a hand facing the room. When a burglar goes across the fingers, that trips the alarm. False alarms are prevented because most burglar alarm motion detectors require two or more fingers to be crossed. This makes motion detectors bad occupancy detectors.

The solution is a combo motion/occupancy detector. I don't know the model, but my Optex sensors can perform both functions. It contains an IR sensor AND a microwave detector. The microwave detector is most sensitive toward or away from the sensor, where the IR sensors are most sensitive across the sensor, as I just spoke about. These combo sensors have an additional connection to +12 V or 0 V to tell its its a motion sensor OR an occupancy sensor.

In motion mode, BOTH the IR and Microwave must be triggered to trigger the sensor. This prevents false alarms. In occupancy mode EITHER the IR OR the Microwave will trigger the sensor making it more sensitive. It takes an extra wire, but basically when my alarm is AWAY or VACATION, then the sensor is motion, otherwise occupancy. Again, I can't give you a model number, but these DO exist, and they cost slightly more, but they are worth it.

On motion or no motion, there is a solution there as well. Most recent panels have a crosszoning setting for each zone. Crosszoning means that the alarm will not be tripped with one zone, but rather a timer is started and if a second zone is tripped within the timer period, then alarm. If you have a bunch of motion detectors, this is the best way to go. Its pretty unlikely a burglar in my house wouldn't trip at least two motion detectors. And this avoids the false alarms caused by the occasional spider making its home in a sensor.

So you can use crosszoning to prevent false alarms and still use motion detectors for protection.
 
Thanks for the information Ano. I'd love to know what models Optex sensor you are using. So if you have a chance to check, I'd love to hear back.

Thanks,
 
Thanks for the information Ano. I'd love to know what models Optex sensor you are using. So if you have a chance to check, I'd love to hear back.

Me too. I looked at the Optex web site and I saw their dual technology sensors. However, they never used the term "occupancy" in describing their function. The description implied they used the dual technology as a way to improve on the motion detection function
 
Thanks for the information Ano. I'd love to know what models Optex sensor you are using. So if you have a chance to check, I'd love to hear back.

Thanks,

My mistake. Mine is a Napco C-100STxxxx The xxxx is the submodel and I think mine is LR.

I went to their page, and they may not have that model anymore, but they still have the feature. For example, check the C200AP. The feature is called SMARTER SYSTEM and it is described as "Panel & Sensor Integration Input: Rock solid, automatically coordinates sensor sensitivity with panel status (armed, disarmed, arming in process, etc.)" On my older sensor it was just called "Quick Response Mode"
 
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