Relay not working with Particle photon

[nilesh]

I did the change you said and connected to D^ relay worked fine but when i connected it to the main electricty the relay stops working the Relay red light works well but the sound of the click inside doesnt work and the switch doesnt work.I dont understand,The photn becomes very hot as well

[BulldogLowell]

Cannot understand your run-on sentence. did you say something worked?

edit: you may want to try transistor switching to step up the 3.3V signal from the output pin on Particle to the input pin on the relay

do you have transistors?

[will]

@nilesh please be very careful if you are a beginner working with AC or mains electricity. As @BulldogLowell mentioned, if you have a transistor you can use a digital pin like D6 or D7 to activate it and pass a 5V signal from V_USB to the relay.

Another relevant thread for you:

Are the 5V tolerant digital pins capable of sinking 5V as an output?

Hi, I see that a number of the digital pins are 5V tolerant when configured as inputs. Are these same pins capable of sinking 5V when configured as an output? What current can they handle? I need to drive an external module which uses a PNP transistor (S8550) running at 5V, via D3. Is that possible? Thanks!