The main problem in a smart home is that it is impossible to ensure the reliability of its operation normally, there are always some problems, these may be problems related to sensors, they may be related to devices, they may even be related to the connection, and for example, if it is a cloud solution, then it may be at the most inopportune moment fall off, or if, for example, outside the house, then remote access to the smart home may disappear and then it is not clear how to turn off or check something.

When I make, for example, some sensors, such as temperature and humidity sensors, in order to adjust the operation of heaters or some other devices, such as a fan, I practically have several similar sensors in every room, that is, I use a temperature and humidity sensor from Xiaomi, and there is also a homemade one. The temperature and humidity sensor, which I have built on the basis of attiny85, is battery-powered, and you can also measure the parameters in the room, but the advantage of homemade devices is that you can not only measure these parameters, or you can additionally add, for example, a light sensor. The method of adding it is very simple, it is the cheapest photoresistor, its cost is 5 rubles, maybe 1 ruble even, depending on where to order, I bought a whole pack of 50 photoresistors a long time ago, and they come in one batch with completely different characteristics and you can easily select the necessary parameters. We can also, for example, connect to this sensor, I still have such a sensor in the bathroom, where it can also measure and track movement, it is a passive infrared sensor, which, plus everything else, temperature and humidity and illumination, also tracks movement, and it has a small timeout, which in principle It's very useful, so I use homemade devices a lot, and mostly, of course, I have temperature and humidity sensors.

Therefore, when, for example, I set up the operation of a smart home system so that the heater turns on and off only at a certain temperature, then of course I try to provide these options for operation from different sensors, but it does not always work, because automation itself becomes more complex, it is necessary to provide for the operation of several sensors, if one of the sensors, for example, they practically show temperature everything is the same, but if, for example, you need to measure humidity, then the spread is very large and, for example, Xiaomi shows 65 percent humidity in the bathroom, despite the fact that the sensor is homemade, although it also uses a fairly high-quality and relatively expensive humidity sensor, but it shows 85 percent, it's not very clear who to believe, but of course I trust the Xiaomi sensor indicators more, they are still more industrially made and used by a large number of people, I also have quite a lot of such sensors. I checked with each other and compared their readings, they are basically very close, and I have these sensors working in different conditions, there is a sensor on the balcony, there are sensors in other rooms, therefore, of course, I trust the proprietary sensors more.

But I use my sensors for various reasons, including because of the greater versatility of these sensors, and when checking the parameters, I constantly monitor, especially from homemade sensors, which values are transmitted, I have limitations, if I need to measure a cooler room, then I set from a much lower value to a higher value. high, that is, the range itself, for example, on my balcony is very large, that is, it can be 0 degrees, maybe when the sun is warm, for example in summer, it rises to 40, in other rooms, of course, there is no such temperature difference, and there I track from 10 degrees to 30 degrees, and if the parameters go beyond these ranges, then of course I can no longer use them in scenarios, I still need to double-check.

For example, in the bathroom, my entire fan automation system is built on a homemade sensor, although there is also a Xiaomi sensor there, and for example, in other rooms, if a heater is used there, heater control, then of course I use Xiaomi sensors there because they are more trustworthy, but still, when processing the scenario, I take into account the prescription of the change if the parameter is very ancient, that is, for example, the value has not been updated for several hours, then in this case, of course, I prefer to turn off the heater anyway, because it is not critical, and not to execute this scenario. And if this is critical, that is, for example, on the balcony, I have a temperature there that does not fall below zero, then of course it is wrong to turn off the heating, because if the temperature drops below 0 and something may freeze.

Also, very often, when I was not at home, I tried to connect and check some sensor or turn off some device, it very often did not work, for example, I used OpenHAB for remote access, since it is still using American servers, very often during the day, that is, when we have a day, but it's nighttime, and for some reason, the servers are probably on preventive maintenance or something, and they're unavailable, and it's not possible to control the smart home, so we have to look for other ways to interact.

I also have an additional telegram channel, this is a telegram bot that is configured, which is processed on the smart home server, and so I can still send or execute some command, or receive some parameter from the smart home system, and I also use the Yandex smart home, there are also all these my devices are turned on, and I can either turn on or turn off some devices, or check some sensors remotely.

Very often, also at the most inopportune moment, I may run out of hosting payments, I may run out of SSL certificates, I have been using free certificates quite constantly lately, because the certificate is officially very expensive, for a while I received it through all sorts of promotions, but now it is very expensive to buy an ssl certificate, and because of this I use a free one, but it is given only for three months, and of course once every three months it is necessary to ensure that it does not expire even when I am not at home at that moment, or so that I have the opportunity to replace it, This means taking a laptop with you, for example, and getting a new certificate, or, accordingly, making sure that the certificate does not expire, which is practically impossible, because it expires on a certain day.

Sometimes, of course, it happened when the Internet was turned off altogether, I forgot to pay on time, of course, I can set up an autopayment, but I don't use it and prefer to pay for it myself several months in advance, but it also happened that for some reason I forgot, or even there were cases when the Internet provider simply did not work and The smart home was also unavailable remotely.

In general, when I try to create some kind of automation or connect some kind of device to a smart home system, I still prefer to use solutions that can work even if the smart home is turned off, the smart home freezes, and in other situations, for example, I use wired smart light switches, they can work and in the absence of wi-fi or in the absence of Zigbee, the light can still be controlled, and I've had situations where, for some reason, either it was a mistake or there was some kind of glitch, and I had the script running all the time, and the lights turned on and off many times, which of course was inconvenient for those who were at home, and the easiest solution was to turn off the smart home server so that it would not process these events, and I even used this several times. Because after all, a smart home is not some kind of car that you can get out of if for some reason it doesn't work properly or doesn't drive, but still people live in a smart home and still need to be able to turn everything off somehow and return to normal life.

And when my underfloor heating stopped working, or it was heating up continuously, or when my heater was running continuously, it was also possible to just physically turn off either the underfloor heating regulator, or turn off the heater accordingly, or unplug it altogether if the smart home system for some reason could not process it correctly.

Therefore, I do not have, for example, controlled relays in the electrical panel that allow me to de-energize the apartment either remotely or from the smart home system, because if something suddenly goes wrong or this relay may also not be of very high quality, it may either burn out or turn off, and then the entire apartment will be left without electricity, which It won't be good at all, and if you can turn on an ordinary automatic machine, or even if you need to, you can replace it very quickly, then of course you won't be able to quickly purchase a specialized device and replace it with another one.

Automation in a smart home should be useful and create additional comfort, but sometimes everything goes wrong… The reasons for this, and how to configure everything, see on my channel.