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День томуIn video #300, I postulated that each classroom should have a CO2 sensor against sleepiness. For a few days, we have a second reason that probably created a better business case for your project: The fear of a next lockdown might convince the school and other managers more because CO2 measurements in rooms can also reduce aerosols in the air. I also show why eCO2 sensors are not a good idea for this purpose.
I am a proud Patreon of @GreatScott! , @ElectroBOOM , @Electronoobs , @EEVblog , and others
No Docker, No Microsoft Teams, Zoom, IKEA
Links:
ESP32 mini: s.click.aliexpress.com/e/_AFgYK7 or bit.ly/2ohsawD or amzn.to/2Tp67zX
SCD30: s.click.aliexpress.com/e/_ADEo0R or Digikey
Senseair S8 Sensor: s.click.aliexpress.com/e/_9ymDrl (seems to be better than the MH-Z19)
MH-Z19 Sensor: s.click.aliexpress.com/e/_9897R9
MP3 player: s.click.aliexpress.com/e/_A9jfHH
PAM8403 Stereo Amplifier: s.click.aliexpress.com/e/_A3y6Hv or amzn.to/2Tp67zX
Prototype PCBs: s.click.aliexpress.com/e/_9QWZk7 or amzn.to/2HuXEZO (I used a 3x7cm PCB)
10W loudspeaker: s.click.aliexpress.com/e/_AORPnp
Sketch: github.com/SensorsIot/CO2-Cuc...
DFplayer: wiki.dfrobot.com/DFPlayer_Min...
Birds: www.thingiverse.com/thing:579484
Linear Servo #1: www.thingiverse.com/thing:896781
Linear Servo #2: www.thingiverse.com/thing:317...
CO2 Ampel: www.umwelt-campus.de/forschun...
Other interesting CO2 Monitor Project: github.com/KlausMu/esp32-co2m...
Chapters:
0:00 Intro
1:00 Introduction
1:39 Agenda
2:37 A Fake
3:12 Start of build
4:48 CO2 sensors
9:12 Dangerous CO2 concentrations
10:22 Sensor selection
10:44 System overview
10:56 The animated cuckoo
11:56 Sound system
13:40 Summary
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Supporting Material and Blog Page: www.sensorsiot.org
Github: www.github.com/sensorsiot
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@AndreasSpiess 3 роки тому
A Patreon recommended the Senseair S8 sensor. It is just a little more expensive than the MH-Z19 but more reliable. And it is available on Aliexpress.
@marcrives279 3 роки тому
A quicky video on this S8 would be great! Especially a comparaison on the autocalibration feature.
@julianwolter970 3 роки тому
There is a nice video series from the manufacturer about the S8: ukposts.info/have/v-deo/pmBmbZ6Ip6-T1Hk.html
@letenof 3 роки тому
I recommend CDM7160 sensor, it comes pre-calibrated from the factory and also the long-term drift compensation (autocalibration) algorithm is much more city-friendly (it does not require periodic exposure to 420ppm fresh air, which might be impossible in real-life situations).
@fhisg 3 роки тому
It always boils down to: what is "good enough" (for all practical purposes) in order to give an indication when to vent a room. Many claim that a BME680 be sufficient. At the other end of the spectrum you have the $50 SCD30 or the $200 CDM7160 :).
@avamander. 3 роки тому
Should've been named a canary clock. Because it detects gases yknow.
@sundwitzi9225 3 роки тому
I have studied Eco Energy and for room atmospheres we hav learned two limits for air quality: DIN limit = 1500 ppm CO2 Pettenkofer Limit = 1000 ppm CO2 So you are totally right with your recommendation! 👍 And yes - it should be in every classroom!
@AndreasSpiess 3 роки тому
Good to know that I am inside the "official" limits.
@TD-er 3 роки тому
@@AndreasSpiess You may also want to look into the cognitive effects of high CO2 levels. There are lots of research papers which show a strong correlation between cognitive abilities and high CO2 levels. Schools with lower CO2 levels in classrooms show higher scores. Also the reaction time of humans is significantly affected by CO2 concentration. There is a paper about the response time and response accuracy of jet fighter pilots in relation to the cabin CO2 concentration. But it does also affect drivers in a car for example. Most cars have a very dangerous button to set the air circulation to only circulate internal. I have not yet had a car which automatically turns this function off after a while (maybe it's also an indication of the age of the cars I drive), so after +/- 20 minutes driving with 2 adults in a car, the CO2 levels can rise to 2000 - 2500 ppm. This does have an effect on your response time similar to drinking a few beers. So I think there should be much more attention to CO2 levels around you. Now with Covid-19 pandemic, there is quite a lot of attention to ventilation and CO2 sensors can be a good indicator of the amount of ventilation. But sadly that's the only aspect being looked at right now. I'm afraid this will be forgotten as soon as the pandemic is over, while keeping track of CO2 levels around you is quite important for a lot more reasons. For an office space or class room, it should be a no-brainer to actively control your ventilation based on CO2 levels, as it does improve the minds of the people in the rooms. But perhaps we should start installing those sensors in the offices and board rooms of those making the decisions on where to install CO2 sensors.
@BoHolbo 3 роки тому
I was surprised last week, when I read in the news about the german government investing about 500 million Euros to upgrade air ventilation systems in public buildings to combat the spread of the SARS-CoV-2 pathogen. According to the article below, this funding can also be used to acquire CO2 alarm sensors and mobile air purifiers. www.bbc.com/news/world-europe-54599593
@NicksStuff 4 місяці тому
Is there a scale that shows the cognitive loss for a certain concentration of CO2
@smaeschli 3 роки тому
Can we just have a moment of silence for this prime example of interdisciplinary educational awesomeness? Vielen Dank! Und sonnige Grüsse von Bern =)
@AndreasSpiess 3 роки тому
It took me also some time to put all different strings together. But it was fun. More fun than just a display...
@smaeschli 3 роки тому
@@AndreasSpiess Really great idea, much appreciated. Hope it catches on; I've shared it with all the school teachers I know. Keep up the good work!
@mvadu 3 роки тому
Thank you for a well researched video..fact that you tested them for 9months before posting it shows your dedication.thank you sir..
@AndreasSpiess 3 роки тому
You are welcome!
@noweare1 3 роки тому
Very creative job Mr. Spiess. You took a lot of pieces, put them together and they work just great. That what making is all about.
@AndreasSpiess 3 роки тому
Glad you liked it!
@raghavsrivastava2910 3 роки тому
Hello Andreas. 17 year old here in India. For me lockdown is a boon as I don't have to put my brain into school stuff like literature, history and other useless subjects. I can learn interesting stuff like math,physics and ofcourse about sensors and microcontrollers, SDR, antennas and more.
@Dust599 3 роки тому
and you will never learn to socialize and end up alone.... school is needed.
@AndreasSpiess 3 роки тому
@Raghav: As long as you learn something useful I like it!
@raghavsrivastava2910 3 роки тому
@@Dust599 yes for sure sir. But I wanted a break.
@raghavsrivastava2910 3 роки тому
@@AndreasSpiess Thanks a lot for replying to all of my comments. ❤️
@NiHaoMike64 3 роки тому
@@Dust599 So socialize online. And at hackerspaces once it's safe to do so.
@PhG1961 3 роки тому
Interesting explanation about how the sensors work. Great ingenuity and entertaining. As usual.
@AndreasSpiess 3 роки тому
Glad you enjoyed it! It was also fun to build it.
@roelskiunplugged1134 3 роки тому
As always an excellent video! Fun idea, practical application of sensors and microcontrollers and a project everyone should be able to make. Oh, and excellently produced with current important topic. I love it!
@AndreasSpiess 3 роки тому
Thank you very much!
@stefkpl 3 роки тому
For the audio player, you can use the internal amplifier up to 3W mono. I use it for long time :) Good job, thank'
@AndreasSpiess 3 роки тому
It was a little too weak with my loudspeaker for a classroom...
@michaegi4717 3 роки тому
As always your video was very inspirating for me. I plan to build a weather sensor (pressure, temperature, humidity and rain ammount) for some time. I want to collect rain, therefore I need a significant roof surface. When I saw your video I decided to include my sensors to a Bird-Feeder house. By this I might improve the acceptance by my wife :) Thank you for your great videos.
@AndreasSpiess 3 роки тому
Sounds great! It should fit if you use a big house.
@janardankb 3 роки тому
I have an authentic Swiss Cuckoo clock, made by "Loetcher" picked up during my visit to your lovely country!!, I always admire its beauty & handmade, workmanship!!
@AndreasSpiess 3 роки тому
I did not know we have Swiss manufacturers! Thanks for the tip.
@Uncle-Duncan-Shack 3 роки тому
This video is lovely, multidisciplinary and very educational. I have some servos, they are very good to keep in the maker's lab. I am thinking of buying one of the lightning detector modules, and when strikes are within a certain distance the mains to my ups in my lab is disconnected. I have a ups with 400 AH of storage, it's particularly important for the 3D printing and being able to carry on working if there's a power outage. So much to do. And so much inspiration from you. I thank you for that. Best regards, Duncan, South Africa.
@AndreasSpiess 3 роки тому
Fortunately we do not have a lot of power outages here. But we also have plenty of projects waiting ;-)
@RalfVogler 3 роки тому
Nice project for classrooms! It's not easy to make it unobtrusive but still remind you from time to time. I first checked CO2 in Chronograf, then used a pcb strip with 8 WS2812 (only 0.50$) with a green to red gradient plus Alexa announcement once levels are below 450 ppm again. Then I moved to just showing the value from mqtt in the status bar (bitbar on macOS, own program on Windows).
@AndreasSpiess 3 роки тому
Then Guidos project is probably a good thing. Just showing the values and a color if it is bad.
@tonysfun 3 роки тому
Very good idea! Again, you are the BEST Andreas! And you have a heart the size of a mountain! Thank you again!!!
@AndreasSpiess 3 роки тому
We will see if it helps somewhere. I parts of Germany they are obliged to add Co2 sensors in classrooms.
@tonysfun 3 роки тому
@@AndreasSpiess You are a great person, smart and with lots of good deeds you're giving away just proves how great character you are! Good Karma will come back to you many times multiplied over and over! I'm so lucky that I found you on the maze of the Internet!!! Thank you, thank you and thank you!
@jotaefearango 3 роки тому
Thanks. Very good job Andreas.
@AndreasSpiess 3 роки тому
Glad you liked it!
@jmaguilarr 3 роки тому
I love this proyect, thx
@AndreasSpiess 3 роки тому
You are welcome!
@WD40651 3 роки тому
Just in time! I'm making similar project right now.
@AndreasSpiess 3 роки тому
Good luck!
@philliptoone 3 роки тому
Me too. I'm making a device for OSHA that will capture an air sample when the level of CO2 exceeds threshold levels. The current sensor I'm using has a diffusion related delay time that is unacceptable. Maybe this new sensor will help?
@bioport1 3 роки тому
www.instructables.com/Giant-Analog-CO2-Meter/?amp_page=true U might find my design interesting...I tried to put it in a kids science museum here but unfortunately “co2” has been politicized in the US ...they declined
@yahmk3978 3 роки тому
Thank you!
@AndreasSpiess 3 роки тому
You're welcome!
@gacherumburu9958 3 роки тому
Thanks for the info..👍
@AndreasSpiess 3 роки тому
You are welcome!
@seanchallenge 3 роки тому
Excellent video thank you
@AndreasSpiess 3 роки тому
You are welcome!
@avejst 3 роки тому
Fantastic project Grat idear Thanks for sharing :-)
@AndreasSpiess 3 роки тому
Thank you!
@electronic7979 3 роки тому
Very good
@AndreasSpiess 3 роки тому
Thanks!
@WacKEDmaN 3 роки тому
good job Andreas!
@AndreasSpiess 3 роки тому
Thank you!
@michaelkeller5008 3 роки тому
Hoi Andreas, hab das Video mal an die hiesige Schulverwaltung geschickt; ev. wird es ja nachgebaut, ist ein klasse Projekt :-)
@feda9343 3 роки тому
Hallo Michael Keller - ich stimme zu: Ist ein klasse Projekt - aber wir werden generell in den Klassenzimmern keine Kuckucksuhren installieren! Wir benötigen eine Kosten-effektive Lösung.
@michaelkeller5008 3 роки тому
@@feda9343 Och - pro Klasse ein solches Projekt, Fächerübergreifend "Werken", "Naturwissenschaften", "Informatik", oder sogar Klassen-übergreifend gemacht, für jedes Zimmer ein solches Teil (kann ja auch ne Lampe sein, die Rot aufleuchtet etc; Vogelhäuser für die Primarstufen, Lampen für Mittlere, für Oberstufe etwas "Aufwendigeres"). Drückt die Kosten gewaltig, bsp. die unteren Klassen bauen die Vogelhäuser (oder was es auch immer sein wird), das Material aus dem normalen Werkunterricht genommen. die Mittelstufe macht Lötarbeiten usw, Oberstufe die Programmierung. ...allenfalls braucht man dann pro Schüler der Schule einen Euro (!) um die Sensoren kaufen zu können. (lass es zwei Euro sein...) - aber finanziert aus dem üblichen Unterricht. In Verbindung mit dem Stufengerecht optimierten Unterricht ("Warum machen wir das") ein Lerneffekt mit Komfortverstärkung für die Kids, das die Mehrkosten allemal wert sind!
@AndreasSpiess 3 роки тому
Wenn ich die "professionellen" Sensoren sehe bezweifle ich ob die billiger sind... Aber sicher schneller beschaffbar.
@torftee2235 3 роки тому
Prima Idee! Danke für die tollen Videos!
@AndreasSpiess 3 роки тому
Bitte, gern geschehen!
@mawamatakama5150 3 роки тому
I am somewhat dissapointed that Schwarzenegger doesn't live in that cuckoo clock.
@AndreasSpiess 3 роки тому
Would need a huge house...
@morganjennings3164 3 роки тому
Nice work 🌈👏
@AndreasSpiess 3 роки тому
Thank you 🤗
@andrewbeasley 3 роки тому
This is a wonderful idea to show youngsters that STEM can be fun as well as useful.
@AndreasSpiess 3 роки тому
I hope so...
@letenof 3 роки тому
I insist on opening both windows and door for proper fast ventilation. For few months I have been using SCD30 and CDM7160 CO2 sensors in parallel, their output is very similar so far. Opening only windows needs few good hours to decrease CO2 level from 1500ppm to 600ppm (big city environment). Opening the windows and the door creates noticeable "wind" that refreshes the indoor air in minutes. I start thinking on forced ventilation solutions (with or without heat recovery).
@AndreasSpiess 3 роки тому
Good to know that my advice works also in reality.
@Parapascal 3 роки тому
I just designed a board for this purpose to use in my school. I decided to use a esp32 nodemcu, a MH-Z19, an optional bme680 and a mems microphone. The Mic is used for the measurement of the noiselevel ( optional). We plan to put it in a small IKEA photoframe and let the pupils designs the front in the art classes. Two RGB Leds shows the CO2 level and the sound level. Of course, we save the measurements in an influxDB via MQTT. Repo link will follow.
@AndreasSpiess 3 роки тому
Cool project!
@Parapascal 3 роки тому
Here is the EasyEDA Project in it's current version. Everyone feel free to use it. easyeda.com/deneaux/classroom-sensor
@peter.stimpel 3 роки тому
Nice idea!
@AndreasSpiess 3 роки тому
Thank you!
@vineetaagarwal4189 3 роки тому
I am actually in the first row today , otherwise even after subscribing i got the notification a week later . And anyways sir your videos are really interesting and informative, i like to watch the old ones too quite a few times over. Keep it up , stay safe :-)
@AndreasSpiess 3 роки тому
Thank you. I am save in my basement, no worries ;-)
@vineetaagarwal4189 3 роки тому
@@AndreasSpiess well thats good :-) , sir is there any way to make a comparator without using op amps?
@AndreasSpiess 3 роки тому
You can build one using transistors.
@vineetaagarwal4189 3 роки тому
@@AndreasSpiess sir can you provide a schematic?
@vineetaagarwal4189 3 роки тому
@@AndreasSpiess I searched the whole internet , tried myself but couldn't come up with a working circuit
@antiskim01 3 роки тому
Useful video!
@AndreasSpiess 3 роки тому
Thank you!
@sukihirako7240 3 роки тому
Hi Andreas : great tutorials !! we enjoy it with our class. Just a little question ? what about callibration on these sensors ? do we need to calibrate them after a few years and if so : how to do this ? of just swap the sensor maybe ? Thx for the reply and please keep posting these great tutorials !,
@AndreasSpiess 3 роки тому
You can switch autocalibration on. Or you put them outside where the CO2 is around 410 ppm
@sukihirako7240 3 роки тому
@@AndreasSpiess thx andreas, so if i understand correctly, we just have to take them outside once a year and the the auto callibration will do the rest ?
@CreativeJE 3 роки тому
this is really awesome :)
@AndreasSpiess 3 роки тому
Thank you!
@rolandtemmerman1100 2 роки тому
CO2 concentrations above 2500 ppm cause a decrease in concentration and laziness. As a bioeffluent, CO2 is the easiest parameter to monitor the IAQ and to control the ventilation demand if a mechanical ventilation system is available (demand controlled ventilation). VOCs are determined by the occupancy rate of people in the room as well as by furniture (e.g. formaldehyde), mould (!) and various cleaning products. CO2 is therefore the better choice in classrooms because the collective breathing volume of those present is the determining factor. I have installed CO2 meters in many classrooms already for Corona, in the years 2010-2015. Senseair S8 sensors were reliable and stable over long periods of time, MH-Z19 not so much because they drift upwards (even when placed outside for months for checking). Regards
@AndreasSpiess 2 роки тому
Thank you for the additional info! It seems that schools in Germany bought a lot of such ready-made sensors. I think it would have been a good idea to build them and learn... In Switzerland they still did not decide on what to do. If i look at the increasing numbers we probably still have a lot of time to decide ;-)
@MoraFermi 3 роки тому
Oh nice, I've been looking for a good CO2 sensor.
@AndreasSpiess 3 роки тому
Check also my pinned comment.
@averestless 3 роки тому
I am Digital. I see a video with a Swiss accent, I click.
@AndreasSpiess 3 роки тому
Thank you!
@Thamli 3 роки тому
Ohh! A farting machine when the CO² values reach high values. People usually open windows anyway when someone farts. 👌🤣
@AndreasSpiess 3 роки тому
Great. A „natural„ user interface.
@johnbuchman4854 3 роки тому
CH4 (methane) != CO2 (tree food)
@bobobo1618 3 роки тому
I've been refreshing the SCD40 page for months, how did you manage to get one!? Also you need to look very carefully at the auto-calibration cycles for different CO2 sensors when deciding which to buy. Sensirion's cycle looks for closely matching readings over a period of a couple of weeks, which is my favourite. Many of the other sensors (including the Sensair S8 IIRC) have auto calibration cycles designed for HVAC systems that have a daily fresh air purge, which ensures a consistent low reading every 24h and base their calibration cycle on that assumption. In residential applications you won't always have such a consistent low reading and so your baseline can be skewed by a bad auto calibration. You can also consider adding a pressure sensor and feed the readings to the SCD30. The sensor is cheap and integration is easy. I need to try switching it off and see what happens sometime though, I don't know what the real impact is. The temperature and humidity sensor is also super important. The readings can change drastically if the temperature and humidity values are wrong. /rant
@AndreasSpiess 3 роки тому
I have a pressure sensor added in my setup (the BME680). But I think it does not change too much for our purpose. Calibration here (and also in class rooms should be simple: During night the air should be close to 400 ppm. This is what I had a look and the Senseair and Sensirion did it quite well. The MH-Z19 sometimes did not return to this level.
@haajee1 3 роки тому
Is there a simple ready to go sketch for a co2 sensor with a display? Oh this week did arrive by me a LOLIN TFT 2.4 touch shield for the Wemos. It's cheap and easy because it''s a shield. I think it''s also nice for your projects. So a free tip from me Andreas.
@AndreasSpiess 3 роки тому
Use the example files of the sensors. Should be easy.
@khatuntsovmikhail6223 3 роки тому
в систему жизнеобеспечения мкс входит: «СРВ-К» - система регенерации воды из конденсата атмосферной влаги, «СРВ-У» - система регенерации воды из мочи (урины), «СПК-У» - система приема и консервации мочи (урины), «Электрон» - система генерирования кислорода на основе процесса электролиза воды, «Воздух» - система удаления диоксида углерода, «БМП» - блок удаления вредных микропримесей и др. там кучаи куча датчиков и регуляторов и углекислый газ только малая часть
@AndreasSpiess 3 роки тому
Thanks for the info. I just referred to the increased CO2 levels. So they cannot be dangerous.
@myIvanVideo 3 роки тому
Andreas, thanks for nice video! If talk about comparison Co2 and eCo2 sensor, especially about css811. In css811 datasheet said that "ams advises customers to run CCS811 for 48 hours in the selected mode of operation to ensure sensor performance is stable", and in case Automatic Baseline Correction "The air quality is expected to vary in a typical environment so the minimum time over which a baseline correction is applied is 24 hours". Based on this data we can assume that some more less accurate values we can get from sensor after 2 days after first start. As I understand from your graph, tests lasted 5 days, and result after 2 and even 3 days was't similar real CO2 sensor, what library do you used for tests css811? Maybe there was some problem?
@AndreasSpiess 3 роки тому
My tests run 6 month. I do not think I was the problem. These sensors measure something different.
@nukular2008 3 роки тому
Another idea could be to use a canary instead of a cuckoo. Like the canaries they used in mines to detect dangerous gas levels. Is the CO2 level is to high, the canary falls down from its rung our something and makes a noise.
@AndreasSpiess 3 роки тому
Good idea. I even think my bird actually resembles a canary. But it does not fall down...
@Scrogan 3 роки тому
Was that new sensor a PoE sensor? Be pretty neat to hook up a few dozen about a workplace for easy active monitoring without needing an MCU for each one. I also wonder how easy it would be to make a CO2 sensor like that? Two matched photodiodes and a band-pass or band-stop IR filter is basically all you need, plus a differential amplifier of some sort. Keeping the IR amplitude constant might require feedback from one of the photodiodes to the LED, but that’s not much of an issue either. Then it’s just an ADC and an MCU, with a case. I should see what those IR filters cost.
@AndreasSpiess 3 роки тому
They added a different connectors. But it is not PoE. And it is not easy. Otherwise they would not be able to charge this high price ;-)
@klassichd10 3 роки тому
Thanks for the good idea. I second your insisting to a real CO2 sensor. For more than 30 years I am involved in measuring activities and so, I am fearing noise and cross sensitivities as well. Im my home I am using the power consuming MH-Z19. It has an built in "self calibration" assuming that the lowest value within 24h is 400ppm. This might be valid for a class room but not for every room in your house. ESPHome gives the abilitiy to disable this stuff (ESPEasy and Tasmota did not). I am very interested in the new Sensirion device. Please, keep us informed. Even if CO2 has nothing to do with aerosols it gives a good indication of human-caused degradation of air quality - much better than gut feeling of a teacher. Thanks also for the clarification of Swiss Style Black Forest Cuckoo Clock of Bavarian Clockworks and so on :-)
@AndreasSpiess 3 роки тому
Glad your experience matches. The results were quite clear. The MH-Z19 sometimes did not go back to 400. I will check with ESPhome. So we can hope some sensors will be built in the near future.
@letenof 3 роки тому
The "Self Calibration" feature is not appropriate for all use cases. SCD30 datasheet states that the module must be exposed to fresh air (420 ppm CO2) every 24h, this might be impossible in spaces with permanent people presence or/and poor ventilation. I also use CDM7160 which has a less restrictive autocalibration algorithm.
@klassichd10 3 роки тому
@@letenof Exactly! This is the reason why I am using ESPHome in this application. So, I easily could DISABLE this feature.
@NicksStuff 4 місяці тому
Have you measured the power consumption and "time to accurate measure" of the SCD40? With such a small sensor, it would be cool to make something very portable (to bring to a meeting or dinner) if the power consumption is reasonnable
@AndreasSpiess 3 місяці тому
I do not remember. But you should find this info in the datasheet.
@robertjaeger129 3 роки тому
Of course your video was very interesting AND will be useful:-). For a while I've also been working with a few sensors from Sensirion (SHT85, SPS30, SGP30). Now I hope the SCD40 MEMS sensor will be available to everyone as soon as possible. Are there already rumors when that might be? I'll be back, too (at the latest when your next video comes;-).
@AndreasSpiess 3 роки тому
I have no info about availability. If I will, I will post a link in the description.
@GabrielKleinCH 3 роки тому
What a good idea :) I have a Cuckoo that need to be repaired and improved. Swiss price, but made in china as usual.
@AndreasSpiess 3 роки тому
Mine is really "Swiss Made" ;--)
@jean-marcparatte5564 2 роки тому
Hi, I own a fresh SCD30 (and an old MH-Z19). Have you found a solution to ESP32 I2C clock stretching? It's to experiment phyphox CO2-Monitor.
@AndreasSpiess 2 роки тому
Sparkfun seem to have a library for this sensor which also works on an ESP32. I do no more remember how I did it. But it works
@peut 3 роки тому
Just adding some info on the MHZ19: The MHZ19 also supprts a PWM output which is faster and requires only one digital pin of your choice. Admittedly, this requires some software tweaking to work reliably, but is working fpr me for the last 2 years with no issues. According to the spreadsheet, initial zero ( = 400PPM) calibration should be done by placing the sensor 20 minutes in an environment with 400ppm CO2 levels. For practical puposes, just put it it outside for that period and connect the HD pin to ground for 7 seconds afterwards.Leave auto-calibration on for normal indoor use. Looks like the Senseair is very similar ( both infrared and UART and PWM output) . Not sure why it would be more reliable, construction?
@AndreasSpiess 3 роки тому
I had the Sunrise sensor in my test. It is newer, but I ordered now also an S8 to put it into my setup... I like more I2C or UART than PWM as an interface. But with stable values maybe you just have to measure one or two cycles of PWM to get the right value.
@peut 3 роки тому
@@AndreasSpiess I had to check my old code. After all this time it was a bit fuzzier than I hoped, but I don't average values, I just measure the timing of one period of PWM ( one high and one low) using an interrupt on the PWM pin. Then I apply the formula from the datasheet. UART and I2C are easier to get it to do something quickly and more comfortable in use, but are less efficient if the same ESP8266 is also used for PPM measurements, driving 4 7-segment displays, mqtt results and run a webserver :-).
@zolatanaffa87 3 роки тому
Really interesting project, but at least the sensor should however be positioned at the level of the mouth, or does the 1000ppm level take into account the vertical concentration gradient of co2? Probably Nasa considers the fact that in the absence of gravity the concentration of co2 can be higher because it is distributed in the entire volume of the air, not being subject to gravity. Considering also that the beds are in draft to avoid concentration of co2 around the sleepers, there is certainly a uniform distribution throughout the habitat of the ISS.
@AndreasSpiess 3 роки тому
I do not know how big the gradient is on earth. In my case the sensors are slightly above my mouth.
@zolatanaffa87 3 роки тому
@@AndreasSpiess Your answer comforts my thoughts: the sensor must be more or less at the same level as where the mouth is: in the bedroom at the height of the mattress and in a classroom around 1.20-1.50 m
@Rothammel1 3 роки тому
Hallo Andreas, ist der Kameramonitor neu? von aliexpress? ich wollte vor corona auch mal in sowas investieren...
@AndreasSpiess 3 роки тому
Der Kameramonitor ist einfach ein HDMI Display. Die Qualität ist nicht sehr gut. Aber ich sehe was ich tue...
@petittoto7433 3 роки тому
I am surprised by your comment on the order for the files on the sd card for the mp3 player. You can easily call a specific file by his name. I used it to announce the temperature. I made files for each degree and then called file named for exemple 120.mp3 who say 20°.
@AndreasSpiess 3 роки тому
Did you use the same module? I had some problems and then read what I said. But maybe I am wrong.
@petittoto7433 3 роки тому
@@AndreasSpiess I said "easily" a little bit to fast... now I remember spending some time (hours) to find a solution. If I remember correctly the documentation said to use 2 digit for the repertory and 4 for the file, but at the end 3 digit for the file worked. I used one that look slightly different : www.banggood.com/2Pcs-Geekcreit-DFPlayer-Mini-MP3-Player-Module-MP3-Voice-Audio-Decoder-Board-For-Supporting-TF-Card-U-Disk-IOSerial-PortAD-p-1371683.html?rmmds=myorder&cur_warehouse=CN
@vidadeingeniero3350 3 роки тому
Which CO2 sensor do you think is the best? I need one for my Master Final Project
@AndreasSpiess 3 роки тому
The real CO2 sensors all display similar values. So I cannot tell.
@BoHolbo 3 роки тому
“Better visualization for high CO2 levels?” How about a line from the 1960’s television series “Lost In Space.” Specifically: “DANGER Will Robinson, DANGER!” I believe that it is still easy to find toy robot merchandise from that television series on eBay, so adding a stand (or wall mount) for that robot, and have it flail its arms up and down while playing back the appropriate soundbite from the TV series would be cool. Add some LEDs to mimic the visual effects of the original, and it’ll be awesome! 😎 I don’t think the school kids today will recognize it, but we will! 😏 (At least those of us who are either old enough to have seen the series as a child/teenager, or those who aren’t afraid to fully embrace their inner Sci-Fi nerd.) 😆
@AndreasSpiess 3 роки тому
Good idea. The today's kids probably will also not recognize the Terminator...
@thisone1697 3 роки тому
👍
@jeffking3693 3 роки тому
At the beginning you had the Sensaire 'Sunrise' but then ended up with a S8. The S8 needs more voltage and current (the Sunrise uses a IR LED and is more stable). Why the change?
@AndreasSpiess 3 роки тому
I. Have no S8. A viewer suggested this sensor as an alternative to the MH-Z19. It is reasonably priced and available on AliExpress.
@xfabiosoft 3 роки тому
You did't show a final product image from inside :(
@AndreasSpiess 3 роки тому
Not nice to look at. I Just placed the parts where they fit
@PablumMcDump 3 роки тому
Canary in the Clock. 😀
@AndreasSpiess 3 роки тому
Yes! :-))
@lasersbee 3 роки тому
3:35 sorry not sure what you meant "dashbord for your ????" 4:02.. Could also be inexpensively built with foamboard and hot glue.
@LRTOTAL 3 роки тому
3:35 I think he meant "A dashboard for your school" (In german it's Schule, pronounced shule).
@AndreasSpiess 3 роки тому
Foam and hot glue also would be a good idea. Here many schools work with wood.
@lasersbee 3 роки тому
@@LRTOTAL Thanks.. I thought I missed something
@lohikarhu734 3 роки тому
Oh, too, too cute! But, I thought those things are from Schwartzwald? Good fun!
@AndreasSpiess 3 роки тому
Yes, they are. And Schwarzwald is a part of Germany...
@VolkerKtnbch 3 роки тому
Schwarzwald is close to Switzerland
@stephang5671 3 роки тому
@@VolkerKtnbch That‘s correct, but still on the other side of the Rhein river, in ‚the promised land‘, as my grandpa used to say...
@lohikarhu734 3 роки тому
@@VolkerKtnbch meine Güte! So eine Überraschung! ;-) Viele Grüßen Mr. Chain Creek ;-)
@lohikarhu734 3 роки тому
@@AndreasSpiess but I do remember seeing a store just FULL of those clocks in Bern... Nice idea to mix up some technologies of wood and "sand" ... One Motorola guy described a silicon wafer as "sand that is worth $20 billion per acre"
@ats89117 3 роки тому
Your English is much better than my Swiss, but in English, the last part of the word school sounds exactly like the word cool... Hope this doesn't shock you as much as it shocked me to find out from one of Sabine Hossenfelder's excellent videos that everyone in the English speaking world has been mispronouncing Albert Einstein's name since the beginning! ;-)
@AndreasSpiess 3 роки тому
I make many mistakes, often because we German words are similar to the English words but pronounce differently (probably like Einstein)
@kevinwalters5160 3 роки тому
08:32 Does CO2 ppm reduce with altitude? I thought it was relatively constant for the altitudes humans live at with some perturbation around ground level man-made sources. The sensors need to be able to calculate the number of non CO2 molecules in the air which would be very similar to air density calculations - the pressure, temperature and humidity impact that with pressure declining with altitude.
@AndreasSpiess 3 роки тому
Maybe you google. I found that it depends on hight.
@kevinwalters5160 3 роки тому
@@AndreasSpiess This was the first thing I found earthscience.stackexchange.com/questions/16364/what-is-the-co2-concentration-by-altitude-and-why and there's a similar graph in www.ncbi.nlm.nih.gov/pmc/articles/PMC6263399/figure/sensors-18-04064-f006/ . There could be a slight gradient there but it does not look like 3% reduction per 300m, i.e. 415ppm does not become 290.5 at 3000m (9843ft).
@thesfreader3068 3 роки тому
SOOO much laughing ! No fake laugh here !!! I'll be back (for next video)
@AndreasSpiess 3 роки тому
Glad you liked it!
@NiHaoMike64 3 роки тому
If there's only one window that you can open, putting a fan next to or in the window really helps ventilation.
@AndreasSpiess 3 роки тому
Good idea!
@feda9343 3 роки тому
Why don't you give a perspective when the SCD40 will be available - we are alll waiting for it. Thank you for giving a clear answer that an eCO2 sensor doesn't have the same reliability. The accuracy can be compared in the datasheets - but the ppm values are not available from eCO2 (VOC) sensors.
@AndreasSpiess 3 роки тому
I do not work for Sensirion, so I do not know their plans :-( So you have to ask them.
@feda9343 3 роки тому
Your measurement about the SCD40 looks really good. The cost and availabilty are important - hopefully Sensirion can give an answer - actually the with SCD30 (as a reference ) they make a lot of money...
@AndreasSpiess 3 роки тому
The SCD40 should be cheaper, they said.
@markusm.4556 3 роки тому
After pulling the HD pin of my MH-Z 19b to GND for 7 sec for hardware calibration and left it outside for approx. 30 min., it never showed more than 405 ppm again, independent of position or low long the windows are close. Has anyone an idea how to get it back to work? Or did I kill it by my calibration attempt? Auto calibration is disabled according to my Arduino sketch.
@letenof 3 роки тому
It depends on what "outside" means. If it is a polluted city it will be much higher than 400ppm and inside levels can be comparable.
@markusm.4556 3 роки тому
@@letenof in the past it showed approx 400 ppm outside and 600 up do 1800 inside. But with auto calibration enabled the values drifted over a few weeks and the readings outside never dropped below 800 anymore. This is why I tried the hardware calibration.
@silous8563 Рік тому
Hi, Which sensor would you select in 2023 ? SCD40 ? Tchüss
@AndreasSpiess Рік тому
I did not look into the matter after Covid...
@iLoveTheSyncButton 3 роки тому
Why not the cheap mq135 sensor?
@letenof 3 роки тому
This cheap kind of sensors are not sensitive to low gas concentrations, they react when the level is already too high (for example 10ppm low limit, when good expensive sensors react to ppb values).
@AndreasSpiess 3 роки тому
As I said: These sensors do not display useful readings for "used air"
@berndeckenfels 3 роки тому
The question is if reacting to different human exhale products not only the CO2 might be even better for aerosol concentration (anyway both charts looked not very promising)
@AndreasSpiess 3 роки тому
It is more about not mixing non-human odors (like pizza cooking) or soldering in my case. Co2 seem sot be very human.
@berndeckenfels 3 роки тому
@@AndreasSpiess ah yes good Point, but venting solder fumes is also a good idea
@tommihommi1 3 роки тому
You forgot to put the chapters in the description :)
@AndreasSpiess 3 роки тому
You are right! Thank you. Now they are there.
@philliptoone 3 роки тому
7:14 photo-acoustic effect
@AndreasSpiess 3 роки тому
What is wrong with it?
@philliptoone 3 роки тому
@@AndreasSpiess nothing. I just wanted to make a link in the video to there you talked about this technology for future reference.
@AndreasSpiess 3 роки тому
Aha. I did not put it in the chapters because it is in the middle of the sensors and I said it can be skipped...
@feda9343 3 роки тому
Today I received feedback from Sensirion: the SCD40 will be available beginning of 2021. The price will be about the same as the SCD30 :-(
@AndreasSpiess 3 роки тому
In one of their presentation it was written that it should be cheaper...
@bepstein111 3 роки тому
Andreas, it's 2020, every slicer worth it's salt can resize a model!
@AndreasSpiess 3 роки тому
I think that is what I said (without the 2020, of course) ;-)
@bepstein111 3 роки тому
@@AndreasSpiess Oh you did, just with a hint of uncertainty, that's all! No worries =]
@AndreasSpiess 3 роки тому
I usually do not tell things if I do not know. This was the reason for my wording...
@bepstein111 3 роки тому
@@AndreasSpiess fair enough, good stuff!
@McTroyd 3 роки тому
I have my grandfather's cuckoo clock. I think it needs the Schwarzeneggar mod! 🤣
@AndreasSpiess 3 роки тому
:-))
@smrqdt 3 роки тому
Surprisingly that’s not the first bird-based CO2-Sensor, the radio show Netzbasteln at Deutschlandfunk Nova radio made a „CO2-Narienvogel“ with a canary that topples from the pole if the value gets to high. :D www.deutschlandfunknova.de/beitrag/atemluft-co2-ampel-basteln-fuer-innenraeume-als-corona-schutz The problem with MP3 players using the order of file creation on the file system also happens with some commercial products, there are tools for resorting the file system table following the alphabetical order, e.g. fatsort for *nix CLI. I guess klickibunti (is this word translatable?) GUI programs for Window also exist.
@AndreasSpiess 3 роки тому
Some other viewers also suggested to use a Canary because of history. I was not aware of the fact that they were used for that purpose. But then it should fall down if there is too much CO2 ;-) Thanks for the tip about the software.
@AerikForager 3 роки тому
Historically canaries are associated with hazardous gas detection in mining, why not a canary?
@AndreasSpiess 3 роки тому
Somebody said that the bird I used actually is a Canary. But it does not fall down...
@Electromakerio 3 роки тому
Cool project! We would love to see you publish a write-up over on Electromaker.io!
@AndreasSpiess 3 роки тому
I am a UKpostsr because I do no more write ;-)
@amadeussorro797 3 роки тому
I do like :o)
@AndreasSpiess 3 роки тому
Thank you!
@pascalboudalier1518 3 роки тому
By the way. I latched on the rule on hand in pocket
@AndreasSpiess 3 роки тому
Very good!
@Helli__ 3 роки тому
Imagine an Arnold Schwarzenegger CO2 cuckoo clock. Instead of a cuckoo there comes a Arnold head out screaming "Aaargharghaargh!!!"
@AndreasSpiess 3 роки тому
Also a good idea. Maybe you can buy a carnival mask for that purpose...
@wonder7798 3 роки тому
What abut when wearing the mask? Behind the mask
@vidhill 3 роки тому
If I was to make this, I would have a bird on a perch, and have it fall off its perch if the CO2 goes above the threshold Like the canary in the mines.. :D
@AndreasSpiess 3 роки тому
Good idea!
@Netzbasteln 3 роки тому
Birds are great interfaces!! Did you know we built the "CO2narienvogel" in our Radioshow on german national public radio in September? Just like a canary bird in a coal mine it falls down when CO2 level is too high. We're using the same SCD30 but an ESP8266. Show is here: www.deutschlandfunknova.de/beitrag/atemluft-co2-ampel-basteln-fuer-innenraeume-als-corona-schutz Github Code: github.com/netzbasteln/co2narienvogel Viele Grüße!
@isilverboy 3 роки тому
2:35 ... looool
@AndreasSpiess 3 роки тому
:-)
@spreeuferberlin 3 роки тому
:)
@pascalboudalier1518 3 роки тому
Garde ton humour .. greeting de l'autre côté des Alpes
@AndreasSpiess 3 роки тому
Merci beaucoup!
@mackubecka 3 роки тому
Thanks for a great video. I'm just in the almost same project for school and I just finished mu CO2 level project for my LAB - indication of CO2 is by colors of LED strip. I used Desk Stranding lamp from PrusaPrinters project (some pictures here www.prusaprinters.org/prints/40386-desk-stranding-the-death-stranding-desk-lamp/comments#comment-47597). I'm using sensors from Netatmo Weather Station and using Node-RED and HomeAssistant. Next project is to use real CO2 sensors and color display with ESP32. Another CO2 related gadget could be SmarWi project from Vektiva (vektiva.com/en/). I'm using it for a 2 years for ventilation in my bedroom (works with EU windows ventilation) and I can recommend it.
@AndreasSpiess 3 роки тому
Cool project!
@drmocm 3 роки тому
Für die, die sich dafür interessieren, wie sich so eine CO2 Ampel im Schulbetrieb bewährt hat: www.heise.de/news/CO2-Ampel-Erfahrungsbericht-aus-der-Schule-4932471.html
@AndreasSpiess 3 роки тому
Danke für den Link!
@hapsutakki 3 роки тому
I would like the design to be a bit more "gripping", like the cuckoo clock from Werner Herzog's "Nosferatu": ukposts.info/have/v-deo/n4qBaG-tb3-Sso0.html
@Thamli 3 роки тому
Also, "I'll be back" for kids? Kids in the '80 maybe. The kids don't know this reference 😉
@AndreasSpiess 3 роки тому
Maybe you are right. This was more for the viewers of the video ;-)
@michaels3003 3 роки тому
I guess, they will have to watch the movie/film first. 😎
@joelvale3887 3 роки тому
Can you design something that detects when Politicians are lying about the Covid-19 ?
@AndreasSpiess 3 роки тому
Here in Switzerland we do not elect lying politicians. We do not like such people.
@mvadu 3 роки тому
May be you should export few of them to other countries as well
@thesfreader3068 3 роки тому
@@mvadu As a guy with a French accent, I'd think unlying politicians would be quite welcome here too.
@gregstinkertown 3 роки тому
Great video! I built a simple interface for the MHZ19 github.com/gcormier/co2home. I use this with esphome. I am curious for pricing on this new sensor. The MHZ19 is pretty good once I got it figured out for the price.
@mr.b.1589 3 роки тому
it is not heavier... grr....
@AndreasSpiess 3 роки тому
??
@mr.b.1589 3 роки тому
@@AndreasSpiess 1kg CO2 has the same weight as 1kg air! CO2 has a higher density.
@LordHog 3 роки тому
Will you ever get a "join" subscription to your channel? You should apply for one. I am sure many, like me, would join!
@tbbw 3 роки тому
11:25 Haha to a swedish person that can says "Silicon Beer" since the word "ÖL" means beer.
@AndreasSpiess 3 роки тому
So I learned something new for my next visit to your country.
@mahudson3547 3 роки тому
No brewing in the lab!
@AndreasSpiess 3 роки тому
Just drinking ;-)
@frodobaggins169 3 роки тому
Too much liability! You will not be able to get any liability insurance even if the school and/or students couldn't afford it. It would be like driving with out car insurance. Just the chance of something happening would be a nonstarter. As for as a class project good idea. As for as a safely appliance, can't work! That's my opinion formed from years of being sued by the life sucking lawyers.
@AndreasSpiess 3 роки тому
That is why I asked my daughter to become a lawyer. Good to have one in the family...
@frodobaggins169 3 роки тому
@@AndreasSpiess I'm sure you ment well, be careful what you wish for.
@DanielSMatthews 3 роки тому
I'm fairly sure that CO2 does not making you sleepy, in fact it makes you breathe more rapidly at concentrations that are relevant, but carbon monoxide is a very different story. Certain sulphurous gases caused by people's furtive emissions may also make people drowsy.
@AndreasSpiess 3 роки тому
AFAIK they made tests about decision making and found a degradation with higher concentrations. But I am no medical doctor ;-)
@DanielSMatthews 3 роки тому
@@AndreasSpiess Look up the data generated by studying performance of submarine crews. It is the oxygen levels that matter more, plus VOCs, and your body can't directly detect them in the same way it can CO2. i.e. You need an O2 sensor.
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