Yes it have.
NodeMCU V3 has a pin GND and VU below of A0.
This is the correct picture for V3. In older picture there you have 2 pins - RSV(reserved)…
This is the correct picture for V3. In older picture there you have 2 pins - RSV(reserved)…
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Hi,
Yes ,Im using the Vu pin to power my relays.
I checked the voltage levels on the output pins, they are changing high to low but the relays are not actuating.
Does the relay activate properly “manually”?
I mean by using a high or low trigger from the power supply?
Yes, It does
Do you have the ground from the relay connected to the ground on the MCU also?
Edit:
And does it trigger HIGH or LOW? - Sorry I didn’t read your revised code, so it triggers LOW side. So as above, make sure your grounds are definitely connected.
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what happened if you connect gnd to gnd relay board and 3.3v from nodemcu board to relay trigger pin?
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And maybe also try changing this:
const int Relay_1 = D1;
const int Relay_2 = D2;
to this:
const int Relay_1 = 5;
const int Relay_2 = 4;
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I have tried this,but Im getting the same response.
So, instead of powering the relays from nodemcu,I tried powering it with a 9V battery, & have regulated the voltage using 7805,but the response remains the same.
Did you try @Blynk_Coeur suggestion also?
Can you get a photo of your board/connections? Or even do a sketch?
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maybe your relay needs 5v to be trigger.
and is only Arduino compatible.
the recent one can be trigger from 3.3v to 5 v.
nodemcu digital pin provide only 3.3v.
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I tried providing 3.3 V from the nodemcu & the relays are triggered.
could you add a led between D1 or D2 and GND with 220 ohm resistor ?
okay did add 2 LEDs for each pin respectively and checked the working.There is no change in the LED.
IF possible, please provide an alternative tried and tested link for automation of 2 devices using blynk app.
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So it looks like it’s the nodemcu that’s at fault on the output side. Do you have another nodemcu to try?
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How EXACTLY did you connect your LEDs?
Pete.
There was some problem with the LEDs, changed them. Connected the LEDs directly to D1 & D2.(excluded the 220k resistance). The LEDs are giving the desired output. I have also completed the IFTTT portion.
Now the problem is working of the relays, even though they are getting the signal, they are not actuating.
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Okay, let’s go back to basics…
If you connect just your PSU/battery to the relays, do they trigger if the signal pin of the relay is connected to the positive supply or is it when they are connected to the negative supply?
Please post the code that you’re currently using, preferably code that just uses the Blynk app with two switch widgets. Also, post a screenshot of each button widget setup.
Pete.
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220 ohms, not k !
220 ohms resistors are needed to limite the current and avoid damages.
so if LEDs blink and relays not triggered, there’s a good chance you need 5v to trigger them , nodemcu is a 3.3 v digital output, not 5v.
even if you supply the relay board with 5v.