Do I need to buy hardware for this tutorial?

No. Everything runs in the browser: Circuitly simulates the board, the components and the code. Real hardware is optional if you want to rebuild the circuit afterwards.

Which components are used?

Arduino UNO board, Relais 1 canal. They are already available in the simulator library.

How long does it take?

About 15 minutes, intermediate level, in 4 guided steps.

What should I know before starting?

The previous tutorial in the series, “Stepper motor”, is enough preparation. No software install is required.

Is the code provided and checked?

The simulator checks your wiring and your code automatically at every step, and shows the commented solution if you get stuck.

All tutorials

3 · Outputs & actuators

Relay and mains load

Intermediate15 min

Goal

Switch a power load safely from a pin.

Why it matters

The relay galvanically isolates the control side from the power side.

What you need

Arduino UNO board
Relais 1 canal

Nothing to buy: every component below is simulated in the browser.

Steps

01Add a relay module on pin 7.
02Declare the pin as OUTPUT.
03Switch every 3 s and print the state on the serial port.
04Note that a flyback diode protects the driving transistor.

This tutorial runs inside the Circuitly simulator: your wiring and your code are checked automatically at every step.

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Frequently asked questions

Do I need to buy hardware for this tutorial?: No. Everything runs in the browser: Circuitly simulates the board, the components and the code. Real hardware is optional if you want to rebuild the circuit afterwards.
Which components are used?: Arduino UNO board, Relais 1 canal. They are already available in the simulator library.
How long does it take?: About 15 minutes, intermediate level, in 4 guided steps.
What should I know before starting?: The previous tutorial in the series, “Stepper motor”, is enough preparation. No software install is required.
Is the code provided and checked?: The simulator checks your wiring and your code automatically at every step, and shows the commented solution if you get stuck.

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