Doubt on a project

I have connected the LED bulb using a relay to the bolt module as shown in the figure:

The task to be done:
Turning ON LED and turning OFF LED using google assistant.

I have referred to a document from
then I have used this command to turn off LED through google assistant

turning on LED using google assistant (command)

I used these URLs to sync the bolt device with IFTTT.

Till this everything was all right. But, when I started operating this project.
I get into trouble, when the STATE in the URL is LOW, then the light is turned ON.
The STATE in the URL is HIGH, then the light is turned OFF.

my question is:
Why this is operating in the reverse direction?


Can you connect the relay in Normally Closed [NC] mode instead of NO mode?

Do revert back if it makes any difference.

yeah, I have done this too. but no result. I’m facing this problem when I connect the bulb using a relay.

when I connect LED, it’s working correctly.

Hi @satyasrinath7,

I have invited @vinayak.joshi to help you out this query. He will be replying to you by today EOD.

Do let me know in case you need further assistance.


I am assuming that you have used an Arduino UNO in your sketch to represent the Bolt WiFi module, as you were not able to find the Bolt WiFi module in your sketching software, you have used the Bolt WiFi module, and not an Arduino UNO for the actual circuit, and that you have connected the Relay input pin to GPIO pin 2 of the Bolt WiFi module directly. (You have marked GPIO 2 of the Arduino). Please correct me if my assumption is wrong.

You need to test whether the relay is compatible with the Bolt WiFi module. To do this:

  1. Disconnect the Bulb circuit.
  2. Connect 3.3v and Gnd Pin of the Bolt WiFi module to the relay’s supply and Gnd pin respectively.
  3. Power up the circuit.
  4. Tak a male to male berge pin connector, and use it to connect the 3.3v pin of the relay to the input pin of the relay without disturbing the other parts of the circuit. Then use the same berge pin connector to connect the input pin of the relay to the gnd pin of the relay.

If your relay makes a switching sound, it is compatible, if not you need to get a different relay.

Please do this test, and confirm that the relay is compatible.

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Sure sir, I will get back to u soon.

Previously, I have used a double channel 12v relay. At present i have replaced 12v double channel relay module with a 5v single channel relay module.
after replacing the relay, the code and circuit worked perfectly.
But i am just curious to know that what is the problem with the 12v double channel relay module?

Hi @satyasrinath7,

@vinayak.joshi will be helping you out with this query by today’s EOD.


12v relays normally require about 4 to 8v of input to activate.

5v relays generally require take 3 to 5v input to activate.

This is regardless of the power supplied to the modules.

Since the Bolt WiFi module gives an output of 3.3v, even when the pin is HIGH, the 12v relay will not activate, where as the 5v relay will activate.

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Thanks for clarifying my doubt sir.