I’ve recently been getting some false motion alarms on my Concord 4 (hardwired sensors). At first I thought it was balloons, but ruled that out by moving them to another room. Then thought it might have been pets but the sensor was supposed to have small pet immunity, and a camera on the pets reveals no major movement
Then it occurred to me… could a WiFi access point within a few feet of the sensor be interfering with the motion sensor, enough to throw an alarm condition? The access point is behind the view of the sensor with an interior wall in between, so I would think it wouldn’t cause a false alarm. Any others have experience with this?
Also, this isn’t ideal long term but until I get it figured out, is it possible to arm my system via the alarm.com app and bypass the motion? When I select “force bypass” the Away option gets greyed out.
Then it occurred to me… could a WiFi access point within a few feet of the sensor be interfering with the motion sensor, enough to throw an alarm condition?
Typically, it takes a change in heat to trip a PIR and not wi-fi signaling.
Check to see if the lens is dirty, spiderwebs/debris/etc can have a negative impact on motion false triggers.
Similarly, motions mounted near HVAC vents or pointed towards windows where the sun can cross the lens path can also trigger false motions.
How old is the motion sensor and what is the make/model?
is it possible to arm my system via the alarm.com app and bypass the motion? When I select “force bypass” the Away option gets greyed out.
Specific sensors cannot be bypassed. When Force Bypass is selected, the only option is Arm Stay. Arm Away is not an option and will be greyed out.
If the Force Bypass option is not selected when sending an arming command, the system protests the arming command for about 4 minutes, but it then bypasses any open zones after that protest period.
I wiped the motion sensor down and set up an indoor camera. Sure enough it went off again tonight when the dog moved around a little. Though she was in her usual spot which has never triggered the motion in 2 years until the last couple weeks.
So I took down the sensor and discovered it is NOT the pet immunity model sold to me by the previous installer, but instead the Bosch ISC-BPR2-W12 (not WP12). It is mind boggling that I’ve had it for about 4 years and these are the first false motion alarms I’ve had in that time.
So case closed I guess. Aside from moving the dog to another room for now, I’ll likely need to get a new pet immune sensor. Perhaps I can repurpose the current sensor in a different part of the house. I’m really frustrated at the dishonesty from the installer but I have already terminated my business with them so it’s not worth pursuing it.
Thanks Tyler for confirming it shouldn’t be interference from the wifi though!
Actually it may not be solved after all. We had another false alarm from motion today while we were out of town. It definitely wasn’t the dogs because they are not at the house. Nothing in the room moved, and all blinds and shades were closed so no sun rays. Heat and air is off so there should have been no air movement. No balloons, etc. I’m truly stumped now.
The only things that have changed recently were upgrading the 3g AT&T modem to a Verizon LTE dual-path modem (with new cat6 line back to router), and adding a WiFi access point a few feet away.
Do these sensors just go bad? If so it was a very short life. What else could I do to troubleshoot other than replacing the sensor? Between the new modem and a new sensor, I might as well have upgraded the Concord to a new Qolsys for not much more cost so I’m hesitant to spend more money on a (barely) older system. I appreciate all your help.
For troubleshooting I added a push notification in Alarm.com to alert me any time motion is detected. I am seeing motion being activated several times overnight and during the day when nobody is in that particular room. However, I am not always being alerted each time I purposefully trigger the motion sensor.
For example, I can walk past the sensor and then out of the sensor area, and get the intended alert. I can wait 5 minutes (and sometimes an hour) and walk past the sensor again and not get an alert, even though the LED on the sensor itself indicates it detected motion. It’s like the motion is not being reset or something, and the time between that has been inconsistent so far. When I check the ADC app, it says the sensor is open.
What is the expected time a motion sensor should remain in the open state before returning to closed when there is no further motion?
For troubleshooting I added a push notification in Alarm.com to alert me any time motion is detected. I am seeing motion being activated several times overnight and during the day when nobody is in that particular room. However, I am not always being alerted each time I purposefully trigger the motion sensor.
This is normal with a motion detector notification when trying to manually trip it. There is an hour delay between the motion detector activating and when it returns to idle status in Alarm.com.
This doesn’t affect how the detector functions locally as an alarm sensor, just in Alarm.com for activity monitoring.
Alarm.com adds this delay so you can see whether activity has occurred within an hour at a glance, otherwise the status of the detector is essentially pointless since it would always be idle except the moment of motion.
Have you popped open that motion detector housing to check if it is clean or did you wipe the outside only? Might be good to check the inside for dust.
Sensors can always go bad, as with any electronic device it can encounter hardware issues, but it’s a rare thing. If you have more than one of those same motion detectors you might try swapping the location of that one and another one. See if the issues follow the specific detector or remain at the location.
I got creative and changed the motion sensor to group 10 (entry/exit door) and enabled both open and close chimes, then cleared the room of any activity. Walking past the sensor - open chime. A few seconds later, clear of the sensor - close chime.
Then… random open and closed chimes all over the place (with no activity in the room). Connected my phone to the suspect AP and maxed it out with a speed test - chimes. Repeated 5+ times and got several chimes but it didn’t align exactly with my wifi activity. I unplugged the AP from the router and repeated the process 5+ times. No chimes. Plugged AP back in and repeated - more chimes.
To rule out possible interference from parallel cables in the wall/attic, I placed a double layer of aluminum foil between the AP and the motion sensor. No chimes. Removed foil - chimes.
So it seems that the the culprit may in fact be RF interference from the wifi AP, although if the sensor itself isn’t using WiFi or RF signals at all, why would RF affect it so drastically?
Are there any other hardwired sensors that work well in high-interference areas that I could consider? I’m also concerned that if a hardwired sensor is having this much trouble, how much more trouble would a wireless system have in the same environment? I really hope this doesn’t boil down to having to choose between security coverage or wifi coverage.
EDIT: I failed to mention - I did do a quick clean of both the inside and outside of the sensor with some compressed air. I only have one sensor so I don’t have another one to swap it out. Given that the Concord 4 is basically EOL, I hate to spend any more money on it, so I was considering replacing it with a Qolsys system and reuse my existing hardwired sensors, but I’m second guessing that now, at least until I can feel more comfortable that the interference from wifi won’t be an issue. I would appreciate any advice here.
So it seems that the the culprit may in fact be RF interference from the wifi AP, although if the sensor itself isn’t using WiFi or RF signals at all, why would RF affect it so drastically? Are there any other hardwired sensors that work well in high-interference areas that I could consider? I’m also concerned that if a hardwired sensor is having this much trouble, how much more trouble would a wireless system have in the same environment?
I wouldn’t expect this on a wired sensor, and I can’t really answer that question as to why or which model would be better.
I’ve had a similar report from a Google access point which seemingly interfered with a Z-wave device very close by. Even though the radios are not using similar frequency, the proximity seemed to cause the issue. But that is a case of RF saturation seemingly affecting signaling. In this case you are saying it appears to be affecting the sensing element itself.
What wifi access point is this? What is the model number? Does it run especially hot? Does it have an integrated fan?
I wouldn’t expect and would be a little perplexed by RF directly affecting the sensing element of a wired motion.
Can the access point be repositioned away from the detector as a test? Try adding a little distance and see if the same issue occurs.
I am perplexed as well. The AP is a ceiling-mounted UniFi U6-Lite broadcasting on both 2.4G and 5G bands. There’s no fan in the unit and even with heavy usage it only gets mildly warm but not hot. I had enough cable slack to temporarily move the AP about 3 feet further away and that seems to have stopped the false motion triggers but at the expense of some other issues related to moving the AP.
Prior to moving the AP, I did some more experimenting with aluminum foil shielding on both the motion sensor cable and the sensor itself. The AP was about 2.5 feet behind the motion sensor with an interior wall in between. To the best of my knowledge, the interference appears to be coming through the left and right sides of the motion sensor and not from the back side or via the cable.
Aside from relocating either device, do you think replacing the sensor is the best next step?
I wouldn’t expect this to happen, but you’ve certainly tested well enough to infer the cause. Unfortunately due to the strange nature I cannot guarantee any different functionality from other motion detectors. The best resolution would be to keep distance between the devices.
If you do replace it, a wireless motion would be better, allowing you to reposition it away from the AP.
I went ahead and purchased a pair of new pet-immune wired sensors (Bosch ISC-BPR2-WP12) to rule out a faulty sensor, as well as future proofing for the new dogs. It had the same false motion behavior, so I’ve definitely concluded that the problem is due to interference from the Wifi AP. I could move the AP, but the only other available location in the hallway would put it adjacent to the actual alarm panel just behind the wall. I’m a little concerned to do that (thinking to myself, if it interfered with a motion sensor, how much worse would interference with the panel itself be?).
I’m ok with running new wire to relocate the sensor, and I also wanted to add a second motion sensor in another part of the house. The 4-conductor security wire is more expensive than premium cat6, but I have plenty of old solid 23awg cat5 lying around. Is there any harm in using cat5 if I double up and use each twisted pair as 1 conductor (making it a 4-conductor wire)? Or do I specifically need to use stranded security wire?
As far as wiring the sensors, I only have one zone for motion so how would I wire both sensors into a single zone? Can I piggy back off one sensor to the second sensor? I’ve attached a photo of what I have on my existing sensor if that helps.
The 4-conductor security wire is more expensive than premium cat6, but I have plenty of old solid 23awg cat5 lying around. Is there any harm in using cat5 if I double up and use each twisted pair as 1 conductor (making it a 4-conductor wire)? Or do I specifically need to use stranded security wire?
There’s nothing wrong with using the cat5 cable, solid is just more prone to breaking, but generally that shouldn’t be an issue for a stationary alarm sensor where the wire won’t be moved around.
As far as wiring the sensors, I only have one zone for motion so how would I wire both sensors into a single zone? Can I piggy back off one sensor to the second sensor? I’ve attached a photo of what I have on my existing sensor if that helps.
Unless the second sensor was going to be right behind/beside the existing one or on the other side of the wall from it, you would generally run new wire from the wired panel/wired translator location to the new sensor. You can then wire the detection circuit in series at the panel/translator side.
That would mean that one wire from each of the two circuits would connect to the zone input terminals and the other wire from the two sensor circuits would be spliced together.
I have had the same problem with a Bosch Solution 3000 and one of their PIRs. The WiFi router is in high cupboard less than 2 metres from the PIR (very similar height).
I could reproduce the problem by running an internet speed test (using a mobile device in an area of the house with good reception, so the WiFi would have to work hard).
There were several factors involved including; the position of the router in the cupboard, rotation of the router, whether the cupboard doors were open or closed, internet speed, time between tests, who else was using the internet and possibly temperature and humidity. The challenge was the variability of results and intermittent behaviour.
There is also a clothes dryer, dehumidifier and a few other things in the room which were the initial focus of my investigations. We have also swapped out the PIR etc.
I tried putting various materials between the router and PIR sensor and in the end found two small blocks of concrete provided a reliable solution (they were samples from a concrete supplier 10x10x4cm).
When we got a new Fritz router I removed the blocks and had no problems for several weeks until a tradesman came and repositioned the router in the cupboard (incidentally while working in the space).
I don’t have an answer as to why this happens but provide a way reproduce the problem using the internet speed test and a solution by using concrete as a barrier between the router and PIR.
the answer is quite simply, Radio Waves as in the signal from your WiFI are actually still technically a form of light. just as the Infra Red activates your PIR sensors but only through the lens, the WiFi signal penetrates the whole body of the PIR and triggers it. If possible wrap the body of the PIR with aluminium foil to see if you an block the signal
