Obviously you can skip one relay. If you skip relay REL2 you can also skip D2,T2,R3,R4. If you skip relay REL1 you can skip D1,T1,R1,R2

@Jonathan-Roberts said in Simple AC/DC Switch WeMos: @nca78 bummer. So I think 2 options... What if the Wemos is raised off the PCB. That would be almost 5/8". In your experience would that help? And maybe the best option, slide the antenna module straight down,. move the relay up and spin it around so the connections are on the outside edge. I'm trying to make this multi-purpose and allowing both headers to be fully functional to other projects. thx for the advise. 1 would help but not that much. It's already not a good thing to have the transformer just next to it on the side, so you should avoid blocking one more direction with tracks. I don't understand your necessity to have connectors available for something else on the relay that is too high to put anything on top ? 2 sounds like a much better option, make sure you have nothing right and left of the antenna when you move things around. The problem you will have with this layout is the USB in that situation... It doesn't sound like a great idea to me to use Wemos on this board especially for the relay part, it's just a cheap chinese relay with 3/4 components so why not just put them directly on you board to make the layout so much easier ? I have the feeling that you're trying to make things "easier" by using Wemos and its shields, but in the end you seem to lose more than you gain. And neither does it seem "safer" to use their relay shield as it forces you to have extra wires between main of the HLK and relay shield connector.

I will add that these device fits near perfectly into these box: https://www.castorama.pl/produkty/instalacja/instalacje-elektryczne/systemy-i-osprzet-instalacyjny/puszki/natynkowe/puszka-natynkowa-pawbol-klik-ip54-90-x-45-mm.html It's Polish product so it could be hard to fine in other countries but it costs about the 1 EURO!

Hi @koresh - I had a little accident on the AC side :-). I was wondering what values the 2 resistors (TH and SMD) and diode are ? Thanks!

Hi @aramko-aramko. Unfortunately, this model is already sold. You can look at the upgraded version of this device - MDMSNode "Lighting" Rev 1.1.

@nekitoss Hi! Thanks for you input. CUrrently I do not have any plans to change anything on this board. Its created in Eagles CAD which i havent used since i moved to Kicad. I dont even have it installed anymore. The good thing is that all files are included so you can download and change for yourself.

That is what I do, I create a rule to pads with creepage and rely on my calculations. I'm rebuilding my current switch board to make it safer to use in more polluted environment, I need to use one outside (in a box, but better safe than sorry), and in a bathroom. I think that the main problem with the pads and traces spacing is the design constrains. I need to keep it in a 5x5 cm board and that is not easy, especially when you have a AC and DC circuit! I never considered the distance between AC and DC, and that is the main reason for me to rebuild my boards. After reading your post I made some researches, and I found that I had a design problem. Like you stated, I'm not a electrical engineer, and we are always learning

Hi, did you consider redesigning the PCB using mini nrf24l01+ like this: It could compact the size of the whole device. Moreover it would be great to have GND and Vcc (3.3V or 5V), and 4 GPIO (ie. 2 analog, 2 digital) pins led out on the PCB (there are 6 holes on the edge not used as I understand?). It would be great to have an option to connect some additional sensors (I use 2 dht22 sensors for environment monitoring in some projects).

@sundberg84 I was able to do a photo, so the dallas temp, and le33 "mask" is on the opposite side, I think this is the problem. (in your example pictures they are on the good side) No worries, I use currently the newbie pcbs for light switching,