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How do you control a NodeMCU relay?

How do you control a NodeMCU relay?


  1. Attach NodeMCU on Breadboard.
  2. Connect VCC of Relay with Pin 3.3V of NodeMCU.
  3. Connect GND of Relay with GND of NodeMCU.
  4. Connect Pin Signal of Relay with Pin D7 (GPIO 13) of NodeMCU.
  5. Connect one terminal of Bulb (Blue Wire) with Pin NC (Normally Close) of Relay.

How many relays can be connected to NodeMCU?

1, 2, 4, 8, 16 Channels Relay Modules The number of channels determines the number of outputs we’ll be able to control. There are relay modules whose electromagnet can be powered by 5V and with 3.3V. Both can be used with the ESP8266 – you can either use the Vin pin (that provides 5V) or the 3.3V pin.

How do you control a relay module?

Controlling a relay module with the Arduino is as simple as controlling an output – you just need to send HIGH or LOW signals using an Arduino digital pin. With the relay module you can control almost any AC electronics appliances (not just lamps).

How do you supply 5V to relay from NodeMCU?

Connect your 5 V relay supply to Gnd and “JD-VCC” on the three terminal connector. Connect your ESP8266 I/O line(s) to the relevant “IN”(s) on the relay board. Connect your ESP8266 5 V supply and not the 3.3 V to “Vcc” on the ten pin connector. Do not connect Gnd to ground on your ESP8266 board.

How many relays can ESP8266 control?

Program code is simplified – it’s not plug and play, with hard coded configuration, but it uses 4 relays instead of just one. You can easy extend program to control more relays with single ESP8266. Relays can be controlled from anywhere in the world – you just need internet connection.

Why do we use relay module?

The relay module is an electrically operated switch that can be turned on or off deciding to let current flow through or not. They are designed to be controlled with low voltages like 3.3V like the ESP32, ESP8266, etc, or 5V like your Arduino.

How do you control a relay module with an ESP32?

The code to control a relay with the ESP32 is as simple as controlling an LED or any other output. In this example, as we’re using a normally open configuration, we need to send a LOW signal to let the current flow, and a HIGH signal to stop the current flow.

Which is NodeMCU module does Alexa use?

You can easily control light, fan, and other home appliances with the voice commands using the NodeMCU and Relay module. In this IoT project, I have made the Alexa Smart Home Automation system using the NodeMCU ESP8266 & Relay Module.

How to connect NodeMCU digital pin to relay?

Connect NodeMCU Digital pin ( D4) to Input pin of Relay. Download the ” Relay_NodeMCU.ino ” file and open it up in the Arduino IDE. Then Create a new sketch and paste the code below in the Arduino IDE and hit Upload. You can tinker with it if you like based on the application, or just use it as it is.

What kind of power supply does a NodeMCU use?

So, connect the NodeMCU’s Vin pin to 5V and one of the GNDs to ground of the input side power supply. Since I have used a bread board power supply on the output side of the relay module, it may be confusing to understand the connections.

Is the ESP8266 NodeMCU relay module-control AC appliances?

NO (Normally Open): the normally open configuration works the other way around: there is no connection between the NO and COM pins, so the circuit is broken unless you send a signal from the ESP8266 to close the circuit. The low-voltage side has a set of four pins and a set of three pins.

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