Use this forum to chat about hardware specific topics for the ESP8266 (peripherals, memory, clocks, JTAG, programming)

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By Bains
#52334 Hi,

I'm new to IOT stuff. I recently started working on a simple project to switch on/off a lamp using 8266 (ESP-12e) and relay. I'm able to successfully create a web server and control led connected to ESP-12e. When I connect relay to the same pin, instead of led, I can see small led on relay board responding (going on/off) to signal from pin. But when I connect a lamp with relay, then lamp doesn't work at all. Seems like circuit is not complete. I tried 2 different relays and also tried (NC-COM) as well as (NO-COM) combinations, but results were same. It would be great if someone can suggest what's going wrong here. Please find pictures of breadboard attached.
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By martinayotte
#52396 According to picture, this relay board doesn't seem to have a transistor driving the relay.
Am I right ? (maybe you should provide a picture from top and bottom)
If there is no transistor present, the ESP GPIO cannot provide enough current to drive the coil.
In such case, you need to add one.
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By Bains
#52440 Thanks for your reply. I suppose this relay should have transistor as I heard that it can be used as it is. Sorry, I am from programming background so can't confirm. But I do hear a slight "TICK" sound when I toggle the pin status connected to the relay. Please find the pictures of the relays that I have tried attached. Thanks again for your help.
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