The Dark Secret of Smart Sockets and How I Fixed it! (DIY or Buy)

Comments · 748

• HM

  @HMPirates · 3 years ago

  Always take a actual size printout of your pcb before sending out to the manufacturer. That way you can try all the components and size any enclosure you want.

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• MI

  @MichelSatoer · 3 years ago

  You could also add a snubber circuit over the relay-switch to prevent electrical interference noise and sparking. (I have had micro controllers reset because of electrical interference from switching relays)

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• TH

  @therealjammit · 3 years ago

  One thing you may want to try to prevent inrush relay sticking is to use a dual inrush relay circuit. Basically you have two relays where the load contacts are in parallel. One relay has a current limiting in series (resistor will do for testing). You close the current limited relay first then the non-limited relay is energized and bypasses the current limiting. When turning off you open the non-limited relay contacts and then the current limited contacts.

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• AB

  @abrarahmed1269 · 3 years ago

  Hello mate<br>I&apos;ve been loving the content for years now, and have been watching since I was 16. <br>I am now in my 2nd year of electronics engineering degree thanks to your content too!<br>Please keep it up and I love the content!

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• DD

  @ddavid2 · 3 years ago

  I love the way you introduce the topics, and how clear you speak!

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• GE

  @george-broughton · 3 years ago

  Some people have solved this problem using one of the aforementioned relays, but also ensuring that the switching occurs at the zero crossing point in the AC waveform. Though with switch bounce being a factor, it might be worth measuring how long the bounce effect occurs for your given relay before trying it.

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• SP

  @spaideri · 3 years ago

  One thing to note that usually cheap relays are specced to AC currents or to a rather low voltage resistive load. In your tests you kinda have a capacitive load in DC.

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• CO

  @Connie_cpu · 3 years ago

  I&apos;m really excited about the ESP32-C3 for projects like this, it feels more like the next evolution of the ESP8266 than it does the other ESP32 series chips. One nice feature about it is that it has a built-in USB Serial/JTAG port, so by simply connecting IO18/19 to USB D-/D+ you can connect it to a computer and program it without even having to mess with programming pins

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• CO

  @connecticutaggie · 3 years ago (edited)

  Looks like a fun project. &nbsp;As a fellow EE, I do have a couple of things to recommend you consider to increase the life of your switch.<br>First, as an aside, I am also working on a own project that includes an ESP32 - a ceramics Kiln remote temperature monitor. &nbsp;But, let&apos;s get back to you. &nbsp;Here is what I would consider.<br>1) The simplest solution would be to move from a relay to using an AC solid state relay. &nbsp;These always switch when the ac crosses zero so no nasty current transition issues. &nbsp;You could buy one but, I would expect that you would want to make you own one.<br>2) If you really want to stick with the relay, add a PTC thermistor in series. &nbsp;I expect that the high current you are seeing must be due to inrush, not the static current or the circuit would overload. &nbsp;Adding the PTC will limit the inrush current when you turn the relay on and hopefully prevent the contact from arcing.<br>Have fun and stay creative!

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• P_

  @p_mouse8676 · 3 years ago

  A cheaper relay can also be used, as long as a simple soft-start circuit is being used.<br>Either with resistors or with a NTC, to bring down the inrush current.<br>Downside is that it will take a little longer for the devices to get needed energy to power on.

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• TH

  @thesimbon · 3 years ago

  In next revision you may consider a better placement for the poor antenna of the esp8266, as I&apos;m not sure it would like that big ground plane around it 😀

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• BE

  @bentfishbowl3945 · 3 years ago

  I think the reason the small transformer distorted was because most mains transformers saturate a bit with no load. That&apos;s the same phenomenon that makes old school power supplies warm

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