Blynk Nodemcu ;device showing offline in blynk app

HI Team I am using 12v relay with Nodemcu and supplying power 12V to both parts and it seems Nodemcu output pins D5,D6, not able to shut the relay to off mode while pressing through app may be voltage is less from Nodemcu pins as i check with 5V relay and supplying 5v to circuit it seems works fine but on 12v the relay,it may need more power as nodemcu pins, if i disconnect on board then the that relay off but not through the nodemcu programing app. i think nodemcu Digital output high & low means either 0 or full volt but still on 0 it did not turn off the relay light .

HI Pete ,supplying 12V to relay and nodemcu D5,D6 output should switch on off the IN1 and IN2 on relay but it works fine only for 5v relay may be some insufficent power issue which it give through the D5,D6 pins ,i assume digotal output are just signal which relay required so that too seems volatge depenendnt.

The NodeMCU uses 3.3v logic levels, so that’s the maximum voltage you will see on the GPIO pins
Most opto isolated relay boards designed for 5v operation by MCUs can work at 3.3v.

Using a 12v relay with your NodeMCU may have resulted in too high a current drain, which may have damaged either the voltage regulator or the ESP8266 chip. Or you may be lucky and have gotten away with it.

Pete.

Blynk.begin(auth); enough to connection to blynk.cloud. try it.