Timer with relay and Arduino – Open Electronics

By Bianchi Gabriele on August 6, 2022

In this project we will see how to build a programmable countdown timer in the range of 1s – 9999s which can be used in domestic or industrial applications as well as by beginners to learn how to assemble an electronic module and load a program.

During the selected time interval, the system can power a load through a relay on the board. For repeated timings it is possible to memorize the duration of the timing, the end of the time period is signaled acoustically with a “beep” and optically by turning off the LOAD POWER LED.



The wiring diagram is based on the Arduino Nano microcontroller which shows information on an LED display (such as the one based on the TM1637 chip, used in this case, or the TM1650).

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About Bianchi Gabriele