@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!

Please specify what type of transformer you are using.

@bilbolodz see earlier posts in this thread. The node does not support dimming, but it does support zero crossing.

@sineverba it is much to learn and instead of me trying to make a half ok job I would suggest you search SSR vs mechanical relay. I think greatscott did a great Youtube video about it.

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

@nca78 I used the code and it worked well with the remote control.- I can switch a LED (for testing purposes attached instead of a SSR) on and off. If I want to switch the LED with a push button I fail. This is what I have changed: #define RELAY_PIN 4 // Arduino Digital I/O pin number for relay #define RELAY_PIN_2 5 #define BUTTON_PIN 3 // Arduino Digital I/O pin number for button #define BUTTON_PIN_2 7 And this is the serial output I get, after I press the button: This is an ack from gateway 1107867 TSF:MSG:SEND,10-10-0-0,s=111,c=1,t=2,pt=1,l=1,sg=0,ft=0,st=OK:1 Sensor value changed, source=Physical switch, Sensor=111, New status: 0 1107877 TSF:MSG:READ,0-0-10,s=111,c=1,t=2,pt=1,l=1,sg=0:1 1107888 TSF:MSG:ACK This is an ack from gateway 1108520 TSF:MSG:SEND,10-10-0-0,s=111,c=1,t=2,pt=1,l=1,sg=0,ft=0,st=OK:1 Sensor value changed, source=Physical switch, Sensor=111, New status: 1 1108531 TSF:MSG:READ,0-0-10,s=111,c=1,t=2,pt=1,l=1,sg=0:1 1108541 TSF:MSG:ACK This is an ack from gateway

Finally I made the changes to the silk-screen so the orientation of the LE33 and Dallas temp sensor is right. Project updated and sent new revision to PCB manufacturer. The right revision if you want to buy should be Rev 4 which is the latest files (PCB Rev 4.1)