VLC is blacklisting recent Huawei devices to combat negative app reviews | 19mm Momentary Push Button

Pools have come a long way. It used to be you had a pump and if you were lucky it had a mechanical timer switch on it. That was it. Now you have digital controllers and spa jets and heaters. You can even get them that connect to your home automation system. If your pool isn’t new enough to do that already, you can get a range of add-on accessories. For a price. [Rob] paid $500 to get a remote for his pool. It wasn’t even WiFi, just a simple RF remote. In 3 years, the transmitter had burned out ($300 to replace) and he decided he had enough. For $20, [Rob] added MQTT control and monitoring to his pool using an ESP8266. You can see the video description of the project below.

If you can tell me the relation between MOC max or peak amps values and the switched power done by the MAINS BT137 Triac I will be more than happy to hear….

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I would also use a solid state relay. And I would think about gluing the glass plate with high temp silicone to the PCB. This vastly improves thermal contact and so heat transfer which reduces peak temp and thermal lag in the control loop. Also it prevents exposed live wires even in case the glass breaks.

I do not recommend diy 120/240 volt AC in this application. While you are correct that the higher voltage allows lower current draw, you are not proposing limiting the current, which can be very dangerous. If your hands were wet with sweat, you would act as a lower resistance path to any available ground you might be touching. In much the same way a hot dog will cook with 120 AC poet applied to each end, you will do considerable damage to your skin, muscle, and fat tissues along the current path. Use DC power, a larger wire, and maintain the safety margin. One trip to the ER will buy many hundreds of meters of wire and plenty of DC power supplies. Oh, and by the way, I’m an electrical engineer.

It works, but the losses are significantly higher, and if you’re drawing much power you’re going to need heavy, expensive low-voltage sides on both transformers. In a pinch, fine, but if you’re going to be buying them it’s better to spring for a single transformer.

I once started cutting into a wall which the building super assured me had no utilities in it with an old sawzall with the ground pin cut off, woke up on the floor with the saw still going in my hands. I hit a live natural gas pipe but the bad ground knocked me down before I could sever gas pipe and destroy the building, kind of like the freak accident where you get thrown clear since you weren’t wearing a seatbelt and walk away from an otherwise deadly crash. I don’t recommend using ungrounded tools but don’t take anyone’s word, verify yourself!

I heard from an instructor that some guys from the national power company use full PPE when switching on/off old main fuses in domestic installations (230V, 15 to maybe 60A). These things are fully plastic and can be operated by everyone, so no PPE needed, but it seems like they explode sometimes – maybe because of the dust you mentionned.

I agree with you. I would suggest reading about creepage distance to the author and updating the layout after that.

Yes, I get that there are societal differences between Eastern ideals and Western ideals. Please understand that Americans also build cheap crap, too- but being across an ocean makes buying and selling a little different, especially with a language barrier and different societal norms. I’ve been bitten by a couple of misrepresented products before on AliExpress, (RGB mechanical switches that were actually just RGB LED’s), but that was my fault- I didn’t look very carefully, and didn’t do my due diligence.

There is no mention of what powers the module here, and I suspect it is a regular 5V, isolated SMPS. @RobHeffo suggests transformerless power supply, but that is not a good idea, for the current drawn by the ESP the capacitor will be too big. There are alternatives, like this guy, LNK306 : http://www.mouser.com/ds/2/328/lnk302_304-306-179954.pdf . It is not isolated, but the thing is probably the best cost option for such a device.

For example, you can assemble a computer and do anything you want with the low-voltage parts, but opening the PSU and fiddling with that is illegal in many parts of the world. IF the device later catches fire and the insurance company finds out it was modified by yours truly, they can deny coverage, and if your neighbor’s house burns along with yours they can sue you etc. etc.