Installation and upgrade of a motion sensor

This article is not a guide on how to install a sensor, but rather on how to upgrade it yourself for home use. Now motion sensors are sold completely ready for installation. In addition to the motion sensor itself, it has a built-in light sensor and time timer. “So what can be modernized in it if it already has everything?” - you ask? This will be discussed in this article. . .

This article is not a guide on how to install a sensor, but rather on how to upgrade it yourself for home use. Now motion sensors are sold completely ready for installation. In addition to the motion sensor itself, it has a built-in light sensor and time timer. “So what can be modernized in it if it already has everything?” - you ask? One of these upgrades will be changes to the power source of the device itself.

In most cases, these devices use a direct conversion power supply. See picture.

The efficiency of such a unit is negligible! The electricity consumption of this unit will have a significant impact on the homeowner's pocket.As a result, it turns out that the sensor does not help you save, but on the contrary, it helps you spend!

What to do ? - I suggest replacing this power supply with a transformer or switching one. Their efficiency is many times higher. And if you choose specifically between a pulse and a transformer, then the efficiency is greater for a switching power supply. Despite this fact, I still preferred the transformer one, besides, I had to introduce only a transformer into the device, since the rectifier bridge and stabilizer are already there. See picture.

I decided to put a lamp with my upgraded sensor in the kitchen, so that when a person approached the table or just walked in (it all depends on how you need to configure the sensor), the light would turn on.

I installed everything and attached it. See photo:

Next comes the most enjoyable part of all the work - the tests. But here’s the problem: the sensor refused to turn off the lamp! That is, it went out for a second and then turned on. What's the problem here, I thought? And I realized that when the contacts open, a powerful electromagnetic pulse occurs in the sensor, since my incandescent lamp has a choke, and the interference created by breaking the circuit interferes with the operation of the sensor and turns the lamp on again after turning it off. No matter what I did, no matter what obstacles I put in - I didn’t install any suppressing circuits - nothing worked out for me. . .

Still, a solution was found when I found a startup board from a burnt-out economy lamp. According to the starting principle, it works the same as a regular fluorescent lamp. That is, I can replace this heavy throttle and starter with this small board. Then I realized that I could kill two birds with one stone. Firstly, I will get rid of unnecessary interference, and secondly, I will save electricity. After all, compared to the throttle system, the starting system of economy lamps is pulsed.This is why she “saves”.

All. I tore out all the insides and replaced them with this little circuit board.

Now I have a kind of hybrid of an economy lamp with a fluorescent lamp.

I want to say that the Chinese have exaggerated again. Instead of the required 26 watts (as it was written on the body of the energy-saving lamp), it produced about 17-19 watts. And therefore the glow became a little worse than with the throttle.

Along with this, there were several advantages. The first of them is savings, and the second is a quick and smooth start. That is, now the lamp lights up instantly like an incandescent lamp without blinking and without cracking of the starter contacts.

Now all the work is completed, we proceed to repeated tests. Everything works stably. At the bottom of the sensor there are two variable resistors. One regulates the sensitivity of the light sensor, and the second regulates the burning time of the lamp, that is, the time delay by the motion sensor.

I attached the sensor to the bottom of the lamp. See photo.

Thus, he acted not entirely wisely. The light from the switched-on lamp is reflected from objects and hits the light sensor and the lamp begins to blink. I had to abandon the light sensor. I reduced its sensitivity with a variable resistor to zero and the light sensor stopped working. Actually, the thing is necessary, but reinstalling the entire sensor in another place was not entirely practical. Now our device only reacts to movement.

In principle, I'm satisfied. I set the lamp so that when approaching the table it would light up, and when leaving it would turn off after 15 seconds. This time is necessary to ensure that there are no sudden shutdowns when the sensor “gets used” to your presence at the table.

In conclusion, I would like to remind you about security measures.If you are planning to do something like this. All parts are under life-threatening voltage of 220 volts. When working, make sure that the device is de-energized; under no circumstances touch live parts when they are live! After turning off, you must wait 15 minutes and only then start working, otherwise the high-voltage capacitors located in the circuit will not have time to discharge and you may receive an electric shock.