Electronic Alarms and Home Security Devices - FBII security system constantly tripping

Hi. We have a FBII security system that is monitored by an alarm service. For the past 3 years, every 6-8 months, the system will trigger false alarms. We will have to place a service call to the company that install the alarm to come and fix the problem. They will replace window sensors and ask if our house was striked by lightning. As far as we know, our house has never been striked by lightning. After they replace the window sensors, everything will be fine for sometime and then false alarms will be triggered again. The cost for these service calls are getting out of hand. Can you tell me if we can buy these window sensors ourselves and replace them? Do the sensors have to be specific ones or can they be any sensors? The sensors are connected to wires and pressed into a hole drilled into the windows. Thanks.

If you are sure that the alarms are being generated by the window sensors, then there is a quick test. Put your system in chime mode, then go to each window while it is latched and try to move it in various directions. If any of them make the chime activate, then I would say it's an alignment issue.

If you have the cylindrical press fit contacts, what I'm guessing is that the magnet on the moving part of the window frame on one or more windows is just on the edge of it's effective range, and a change in air pressure, a large truck rattling the window, or opening and closing a door in the house may shift it just enough to make the contact open long enough. If so, then there are slightly better models of this type of contact that provide a larger effective gap than the stock model.

If you are getting actual contacts failing open, then they are either getting old enough that they are failing internally, or there may be an issue with the panel itself.

The contacts can be had from any number of sources. Just websearch for security alarm contacts. They will generally run about 3-8 dollars a set.

I don't know if it is definitely the window sensors that caused the system to trigger. But, everytime I have a service call, the tech ends up changing the window sensors and nothing else. I will test the windows as you have suggested and report back. Meanwhile, can you tell me:

1. What I should be measuring to determine the size of the sensor? Should I measure the circumference of the top of the sensor with the wire or the hole the sensor goes into?
2. Do I have to replace the magnet part as well as the wired part of the sensor?
3. When replacing the sensor, will any sensor do or only the FBII sensors? Do I have to worry about any electrical compatibily issues?
4. On the web, I am seeing staggered "T" terminal sensors. Do you recommend them?

Thank you.

The sensors are a set of standard sizes. The most common are the 3/8" pressfits. You only need to change the magnet if you change to the wide-gap design. You measure by the size of the hole.

For a wired system, the sensors are just a magnet activated switch. There's no practical difference between any of the major brands.

There's nothing special about the screw terminal models, they are a standard model, especially for replacements. The only time they can be a problem is if the place was wired with stranded wire instead of solid. If you don't have enough wire to handle easily, it can be tricky to get the stranded into the terminals and clamped in.

MrRonFL, I changed the window sensor and everything looks good. I am also looking to change the motion sensor. Can I replace the motion sensor with any available one in the market? Is there one that you would recommend? We don't have any pets. Do you know what is the typical life of a motion sensor? Thank you.

Practically speaking, as long as it's not damaged, a motion detector will last the life of the system. However, the changes in the technology make changing out motions a good deal, because the new designs are more false alarm resistant, and generally have better features (and often look nicer)

They are a pretty much standard item, and are pretty much interchangeable. Stick with the major names like Optex, Sentrol, Bosch, Rokonet, Honeywell/Ademco, and the like. The main differences are mounting options and case design.

The Dual tech designs that use microwave as well as IR are nice because of the higher false alarm rejection, but do typically cost 20-30% more in a given model line.

It took us almost 6 months, but, we finally bought and replaced our old motion detector with an Optex DX-40 (has infrared and microwave technology). It took this long because I was trying to find someone local that sells wired motion detector. I didn't have much luck. Finally, I had to buy it online. My husband just put it up. After putting it up, my husband said (probably semi-jokingly) that we are now being bombarded with microwaves.

I know that people have big issues with microwave towers and its affect on children. What is your opinion? Is there anyway of disabling the microwave part of the detector? I know I am being paranoid. But, I want the best for my kid.

Check your instruction sheet. Some of the Optex models have a jumper to disable the microwave unit. At worst you can turn the microwave range adjustment down to the minimum setting.

On a reality note, these frequencies of microwaves are stopped by skin or fabric. They are not penetrating, and are in the micro-watt power range. You get more radiation from a CRT computer monitor or television.

Thank you very much.