Connecting smoke detectors to house alarm
-
Also, as you would expect, there are quite a few arduino alarm listening projects out there on the internet, such as:
https://www.youtube.com/watch?v=kLI6XKcR6PYI suppose the one thing to be sure about is that it triggers on the frequency of your smoke/CO alarm and not something else, like a car alarm or leak detector. If mounted nearby to the alarm siren on an interconnected system, then I'm guessing you might also want to include audio loudness as a discriminator.
I see that you already found the mysensors opto-isolator project:
https://www.youtube.com/watch?v=mNsar_e8IsILastly, this is Nest Protect's argument for why they think their wireless interconnect is better than wired interconnection: https://support.google.com/googlenest/answer/9231654?hl=en
So, though I haven't yet checked, it occurs to me that the following might work: have a single hardwired smoke alarm with wireless interconnect (BRK does make these), and maybe replace all the other smoke alarms with with battery powered wireles interconnect (BRK also makes those). Then, the question is: would the wirelessly interconnected smoke alarms trigger a BRK relay that's connected to the one hardwired smoke alarm that is also wirelessly interconnected? I'm pretty sure the answer to that would be "Yes". One possible gotcha (?) from that is that perhaps the one hardwired BRK that includes wireless interconection maybe wouldn't relay its location to the other smoke alarms if it were triggered, but, if so, maybe you could utilize that information to identify it as the triggering alarm since it would be the one occasion when the other alarms might not be able to verbally identify the source. Obviously, this is speculative and would need to be confirmed. It would be a shame if BRK disabled all the location information just because there was a single hardwired (but wirelessly interconnected) smoke detector in the mix.
-
Much to my surprise, Cosumer Reports gave its highest rating of 93 to the First Alert SCO501CN, whereas it scored the Nest Protect at merely 62, because it did not perform well on either carbon monoxide or fast flame spread detection. The SCO501CN is the battery powered, wirelessly interconnected smoke and carbon monoxide detector with Voice location that I had referenced above. I think if the trade-off is between better sensors (First Alert) or better firmware (Nest Protect), I'd lean toward the better sensors, because that is more mission critical.
Except... Gotcha. The SCO501CN it warranteed for only 7 years, and the listing says it should be replaced every 5 years to ensure an effective CO sensor: https://www.firstalertstore.com/store/products/sco501cn-3st-onelink-wireless-talking-battery-operated-smoke-and-co-alarm.htm
which means buying two SCO501CN over a 10 year period instead one Nest Protect. -
Much to my surprise, Cosumer Reports gave its highest rating of 93 to the First Alert SCO501CN, whereas it scored the Nest Protect at merely 62, because it did not perform well on either carbon monoxide or fast flame spread detection. The SCO501CN is the battery powered, wirelessly interconnected smoke and carbon monoxide detector with Voice location that I had referenced above. I think if the trade-off is between better sensors (First Alert) or better firmware (Nest Protect), I'd lean toward the better sensors, because that is more mission critical.
Except... Gotcha. The SCO501CN it warranteed for only 7 years, and the listing says it should be replaced every 5 years to ensure an effective CO sensor: https://www.firstalertstore.com/store/products/sco501cn-3st-onelink-wireless-talking-battery-operated-smoke-and-co-alarm.htm
which means buying two SCO501CN over a 10 year period instead one Nest Protect.@NeverDie
Wow, lots of interesting information. It took me more than a day to process it.
My requirements/needs are a bit different and majority of the proposed solutions do not apply in my case but thank you for your time and effort sharing them with me:- Do not want to rely on internet connectivity or AC power. I already have alarm that can send text without internet being live or electricity being present, it is a service i pay yearly for and i had to buy mobile add-on card. So ring and nest do not apply.
- Thanks to your advice I looked at house regulations and my house has to have wired interconnected smoke sensors, so wireless sensor is not an option for me.
- I think arduino project is too complex for my abilities and needs as I only want to operate a relay to break the circuit when high volume is heard. But i do think filter of some type for microphone may be needed to be included to prevent false triggers with low frequency noise.
My plan for now is
- I couldn't find a listener with relay, majority are wireless and for specific alarm panel, will look more into it.
- Test the sound/light relay switch, if it arrives
- If not successful try arduino alarm listening project
- If not successful change my requirements and look for other solutions.
I think of programming as a layer on top of hardware and every single layer on top of hardware is just another layer where the error may occur. So because of that It is nice to have more functionality with smart devices but they should be separated, this is just my personal view on things and that is why I wouldn't like to go for nest unless somebody with knowledge in electronics does a review and says that they are independent devices inside. But on the other hand there are many functionalities that may outweigh single broken sensor failure.
-
No problem. I had to look into this for my own situation anyway.
I'm not sure what to think of the Consumer Reports test results. It may be true that some detectors detect certain kinds of fires faster than others, but if the price of that turned out to be enduring a high number of false alarms.... is that something that you'd really want? For instance, ionization smoke detectors are known to be much better at detecting fast developing fires, but they are also known to be much more prone to false alarms. AFAIK, Consumer Reports doesn't test the propensity of different smoke detectors to have false alarms. From what I've read, Nest Protect's 2nd generation smoke detector was designed to avoid some of the frequent causes of false alarms (such as insects and shower steam) that other smoke alarms may falsely trigger on, and that's something that the Consumer Reports rating doesn't factor into its numeric rating. i think I like the nest approach of giving a gentle "heads up" when it first starts to detect low levels of smoke rather than doing what most other smoke detectors do, which is doing nothing at all until a higher threshold is reached and then going straight to emergency alarm mode with sirens blaring.
-
No problem. I had to look into this for my own situation anyway.
I'm not sure what to think of the Consumer Reports test results. It may be true that some detectors detect certain kinds of fires faster than others, but if the price of that turned out to be enduring a high number of false alarms.... is that something that you'd really want? For instance, ionization smoke detectors are known to be much better at detecting fast developing fires, but they are also known to be much more prone to false alarms. AFAIK, Consumer Reports doesn't test the propensity of different smoke detectors to have false alarms. From what I've read, Nest Protect's 2nd generation smoke detector was designed to avoid some of the frequent causes of false alarms (such as insects and shower steam) that other smoke alarms may falsely trigger on, and that's something that the Consumer Reports rating doesn't factor into its numeric rating. i think I like the nest approach of giving a gentle "heads up" when it first starts to detect low levels of smoke rather than doing what most other smoke detectors do, which is doing nothing at all until a higher threshold is reached and then going straight to emergency alarm mode with sirens blaring.
@NeverDie
False alarm is a big annoyance and people start to ignore it/not take it seriously. I was lucky or just strange coincidence that no neighbors reported to me when nobody was in the house and windows were closed (no draft) even with ionization smoke sensors. So based on my personal experience I do not expect too many false alarms when away from the house but i do expect them when i am around be it wife with hairdryer triggering it or steam from bathroom or shower (on rare occasions).
It is hard to choose modes when you think of fire in confined space and time you will be alerted to either extinguish it or run away so if nest notifies at the same sensitivity as ionization sensors then I think it is good balance but it all depends on how fast someone will see/act on it.
Lets hope none of us will have sensors triggered by fire or fail to notify us of fire. -
Seems like only way to be sure is to test it with canned smoke or similar. If there's a way for a smoke detector to automatically test itself without that, then that would be awesome. The Nest Protect says it tests itself 400 times a day, but as I wrote earlier: what does that really mean? For instance, only just that it can communicate with the sensor? If so, that would be a pretty weak test. Ideally you'd like to know that the sensor is actually working as intended and able to detect smoke in accordance with its specs. Maybe by detecting dust particles in the air it would have some insight into whether it's functioning or not? So, maybe a particle detector would make a superior smoke detector? It probably would have to run off of mains power though.
-
Seems like only way to be sure is to test it with canned smoke or similar. If there's a way for a smoke detector to automatically test itself without that, then that would be awesome. The Nest Protect says it tests itself 400 times a day, but as I wrote earlier: what does that really mean? For instance, only just that it can communicate with the sensor? If so, that would be a pretty weak test. Ideally you'd like to know that the sensor is actually working as intended and able to detect smoke in accordance with its specs. Maybe by detecting dust particles in the air it would have some insight into whether it's functioning or not? So, maybe a particle detector would make a superior smoke detector? It probably would have to run off of mains power though.
@NeverDie
Please note that below is just my simple view on sensors of any type.
I think any sensor exposed to environment will need some type or form of maintenance/cleaning or replacement. I also do not think that sensor can test itself unless there is other sensor of different type/technology monitoring other sensor.
As you mentioned previously true way to test sensors is using smoke can from time to time as dust particles/moisture/grease may affect sensors of different types. -
Seems like only way to be sure is to test it with canned smoke or similar. If there's a way for a smoke detector to automatically test itself without that, then that would be awesome. The Nest Protect says it tests itself 400 times a day, but as I wrote earlier: what does that really mean? For instance, only just that it can communicate with the sensor? If so, that would be a pretty weak test. Ideally you'd like to know that the sensor is actually working as intended and able to detect smoke in accordance with its specs. Maybe by detecting dust particles in the air it would have some insight into whether it's functioning or not? So, maybe a particle detector would make a superior smoke detector? It probably would have to run off of mains power though.
@NeverDie
Received sound relay switch and connected to my alarm aux power in parallel with pir to supply power, added 100mA fuse on positive dc cable to prevent module making any problems with alarm panel but not sure if i was supposed to do it on negative dc wire.
Connected Normally Closed circuit to relay Com and NC contacts and adjusted sensitivity of microphone and time. Microphone is sensitive to claps but in my case it has to be a loud hand clap to trigger it. It has status led that shows when relay is activated so I can see if it is working on my monthly sensor checks.
Looking at my original intentions I am not 100% there as I am relying on single smoke sensor and its speaker. I think I will wait a few years and maybe something will come up that has relay (not relying on internet) but in the meantime I am happy to have something working and have some peace when I am away knowing that something is monitoring it (ordered same relay module for backup).
Have a good weekend
-
@NeverDie
Received sound relay switch and connected to my alarm aux power in parallel with pir to supply power, added 100mA fuse on positive dc cable to prevent module making any problems with alarm panel but not sure if i was supposed to do it on negative dc wire.
Connected Normally Closed circuit to relay Com and NC contacts and adjusted sensitivity of microphone and time. Microphone is sensitive to claps but in my case it has to be a loud hand clap to trigger it. It has status led that shows when relay is activated so I can see if it is working on my monthly sensor checks.
Looking at my original intentions I am not 100% there as I am relying on single smoke sensor and its speaker. I think I will wait a few years and maybe something will come up that has relay (not relying on internet) but in the meantime I am happy to have something working and have some peace when I am away knowing that something is monitoring it (ordered same relay module for backup).
Have a good weekend
@vecnar If I'm understanding right, your device listens for a loud sound and then triggers on that and only that. So, then the tradeoffs are you want to set the threshold low enough that it triggers whenever the alarm siren sounds, but high enough that it doesn't trigger on false events, like a car honking in the distance or possibly someone dropping something on the floor or a baby crying. Well, I imagine that would work, though you might get occasional false positives. If your device could be dialed in to only trigger on sustained loud noise, rather than bursty noise, it might cut-out the false positive of someone dropping a vase on the floor, or the like. One thing to possibly be wary of is whether there's drift in the sound threshold over time or temperature of the components in your detection device.
Depending on how your alarm sounds, you could maybe improve on that. For instance, if it has some kind of repeating on-off-on-off pattern to the siren, then you could program an arduino to listen for that pattern specifically, instead of just purely level of loudness. I'd wager that would be quite accurate at triggering if and only if your smoke alarm sounds. Otherwise, there are projects out there where you can allegedly "teach" a sensor to identify your particular alarm's sounds.using classifiers. I happened to notice such a project was published just a few days ago: https://www.hackster.io/news/sandeep-mistry-walks-through-tinyml-audio-classification-using-tensorflow-lite-raspberry-pi-rp2040-f4065b654565
-
@vecnar If I'm understanding right, your device listens for a loud sound and then triggers on that and only that. So, then the tradeoffs are you want to set the threshold low enough that it triggers whenever the alarm siren sounds, but high enough that it doesn't trigger on false events, like a car honking in the distance or possibly someone dropping something on the floor or a baby crying. Well, I imagine that would work, though you might get occasional false positives. If your device could be dialed in to only trigger on sustained loud noise, rather than bursty noise, it might cut-out the false positive of someone dropping a vase on the floor, or the like. One thing to possibly be wary of is whether there's drift in the sound threshold over time or temperature of the components in your detection device.
Depending on how your alarm sounds, you could maybe improve on that. For instance, if it has some kind of repeating on-off-on-off pattern to the siren, then you could program an arduino to listen for that pattern specifically, instead of just purely level of loudness. I'd wager that would be quite accurate at triggering if and only if your smoke alarm sounds. Otherwise, there are projects out there where you can allegedly "teach" a sensor to identify your particular alarm's sounds.using classifiers. I happened to notice such a project was published just a few days ago: https://www.hackster.io/news/sandeep-mistry-walks-through-tinyml-audio-classification-using-tensorflow-lite-raspberry-pi-rp2040-f4065b654565
@NeverDie It is located in the center of the house in the room with with the doors and microphone positioned close to smoke alarm to detect noise. It is very unlikely to be triggered by anything from outside or by neighbors and it doesn't pickup low frequency noise. It only activates alarm if we set it, so nobody is at home at that time and at night time i excluded alarm zone that is connected to sound detector.
I positioned ip camera to monitor status led and it hasn't set itself while we were inside either. So I am happy with its accuracy but as per your advice I will monitor its accuracy at different temperature ranges.
Thank you for suggesting Arduino project to try, hopefully someone will benefit from them but in my view this just adds unnecessary layer of complexity and doesn't benefit my setup. -
@NeverDie It is located in the center of the house in the room with with the doors and microphone positioned close to smoke alarm to detect noise. It is very unlikely to be triggered by anything from outside or by neighbors and it doesn't pickup low frequency noise. It only activates alarm if we set it, so nobody is at home at that time and at night time i excluded alarm zone that is connected to sound detector.
I positioned ip camera to monitor status led and it hasn't set itself while we were inside either. So I am happy with its accuracy but as per your advice I will monitor its accuracy at different temperature ranges.
Thank you for suggesting Arduino project to try, hopefully someone will benefit from them but in my view this just adds unnecessary layer of complexity and doesn't benefit my setup.@vecnar :+1: Nice job! I think that I too will mostly stick with my current smoke alarm setup until either prices on the Nest drop to parity levels or something better comes along. Kinda the "if it isn't broken, don't fix it" philosophy. If it turns out that de-dusting my smoke alarms on a regular basis provides 100% anti-false alarm protection, then I may never feel the need to upgrade at all. Meanwhile, I think I will replace my ionizing smoke alarms with photoelectric ones, since photoelectric smokes alarms are thought to have many fewer false alarms.
-
@NeverDie It is located in the center of the house in the room with with the doors and microphone positioned close to smoke alarm to detect noise. It is very unlikely to be triggered by anything from outside or by neighbors and it doesn't pickup low frequency noise. It only activates alarm if we set it, so nobody is at home at that time and at night time i excluded alarm zone that is connected to sound detector.
I positioned ip camera to monitor status led and it hasn't set itself while we were inside either. So I am happy with its accuracy but as per your advice I will monitor its accuracy at different temperature ranges.
Thank you for suggesting Arduino project to try, hopefully someone will benefit from them but in my view this just adds unnecessary layer of complexity and doesn't benefit my setup.@vecnar Epilog: I just now had to replace a couple of the BRK carbon monoxide / smoke alarms because they began their 7-year end-of-life chirp (5 very loud beeps that sound for every frickin minute that passes, I guess just to be sure you drop whatever you're doing and attend to it immediately :rolling_on_the_floor_laughing: ). Anyhow, two nice surprises: 1. the replacements now cost less than the originals did, and 2. the replacement CO sensors are upgraded to last 10 years instead of only 7. So, considering BRK could have us over a barrel because of vendor lock-in, those were pleasant surprises. :smiley:
-
Anyhow, I would say that probably everyone should watch the following youtube video, because in all likelihood, your CO detector isn't working the way you might think or imagine or hope that it is. Also, it turns out there's a strong argument for supplementing the kind of CO detectors in your house that are demanded by building code with at least one additional low-level CO detector (all of which, it turns out, will not be UL listed, because of somewhat peculiar government rules that are in play) :
https://www.youtube.com/watch?v=e_R9NaTRVFEi.e. when it comes to carbon monoxide detectors, being UL listed probably doesn't mean what you think it would, or should, mean. i.e. the very meaning of "UL Listed" for carbon monoxide detectors is different than what it typically is with other electrical or electronic devices.
-
@vecnar Epilog: I just now had to replace a couple of the BRK carbon monoxide / smoke alarms because they began their 7-year end-of-life chirp (5 very loud beeps that sound for every frickin minute that passes, I guess just to be sure you drop whatever you're doing and attend to it immediately :rolling_on_the_floor_laughing: ). Anyhow, two nice surprises: 1. the replacements now cost less than the originals did, and 2. the replacement CO sensors are upgraded to last 10 years instead of only 7. So, considering BRK could have us over a barrel because of vendor lock-in, those were pleasant surprises. :smiley:
@NeverDie
I am sure it wasn't a pleasant experience and i hope it wasn't at night. Great that they do have better and cheaper replacement and no need to move to different manufacturer. It is not the case for me as BRK left Europe but i hope to start looking in a few years hopefully, if they last.
Thank you for sharing video about carbon monoxide. I will pass it on to my friends that have gas boilers/fireplaces. I personally do not have any and all is electrical but I may get one in case surrounding houses produce too much and it gets inside our house.
I am sure you will get at least one low level co for your house, let me know which one will you go for and your findings. I did a quick search to see if any available in europe and one has digital meter "Fireangle CO-9d" and Product Manual
I think this if the information that may be important but to me it looks like to meet some standards but it has display which shows levels and has past 4 weeks worst level also, or so i understood.Between 60 and 90 minutes when exposed to a minimum of 50ppm of CO. • Between 10 and 40 minutes when exposed to a minimum of 100ppm of CO. • Within 3 minutes when exposed to a minimum of 300ppm of CO. -
Well, since you ask, I've been using this model as a low-level CO detector for around 20 years: https://www.kidde.com/home-safety/en/us/products/fire-safety/co-alarms/kn-copp-3/
That because, at least at the beginning, it was one of the few that had a digital display showing the CO level. These days, there are more models which have that. It would be interesting to make a low-level mysensor CO detector/sensor. -
Well, since you ask, I've been using this model as a low-level CO detector for around 20 years: https://www.kidde.com/home-safety/en/us/products/fire-safety/co-alarms/kn-copp-3/
That because, at least at the beginning, it was one of the few that had a digital display showing the CO level. These days, there are more models which have that. It would be interesting to make a low-level mysensor CO detector/sensor.@NeverDie Just to clarify: not the same sensor (obviously, since they degrade with age), but the same model sensor. It's sensitive enough to detect CO in a garage and show a reading after a car starts its engine. I can't say how accurate it is, but it does manage to detect, and it displays a steady declining CO measurement after the car has left the garage.
-
Well, since you ask, I've been using this model as a low-level CO detector for around 20 years: https://www.kidde.com/home-safety/en/us/products/fire-safety/co-alarms/kn-copp-3/
That because, at least at the beginning, it was one of the few that had a digital display showing the CO level. These days, there are more models which have that. It would be interesting to make a low-level mysensor CO detector/sensor.@NeverDie Thank you for sharing the device you use. I am based in eu and 240 V ac and I think i will just pick one with lcd that can show the highest range even without sounding alarm. Just to check if it is of any concern to me.
My wife got candy canes, 7 sets 2xAA battery operated modules containing 40 leds each and i am trying to find a way to power them and wire them to one power source. Reading online it looks to be over complicated with so many things to calculate. This is just a side not not relevant to this post and the reason i didn't reply to your posts.
