Make This Arduino Uno-Based Window Alarm Annunciator
Electronics For You|August 2019
Make This Arduino Uno-Based Window Alarm Annunciator

Presented here is a window alarm annunciator based on Arduino Uno board.

P. Balasubramanian
An annunciator is mainly used in process plants, power plants and industries to monitor various plant conditions to alert operators about abnormal conditions or parameter deviations. It can also be used as a security/fire alarm. The author’s prototype is shown in Fig. 1.

Circuit and working

The circuit diagram of the window alarm annunciator is shown in Fig. 2. It is built around Arduino Uno board (board1), seven LEDs (LED1 through LED7), three tactile switches (S1 through S3) and a few discrete components.

This annunciator has seven inputs connected across connectors CON1 through CON7 for initiating the alarm through normally-open (NO) contacts. There are also three input switches (S1 through S3) for test, acknowledge and reset. There are eight outputs, out of which seven are connected with LEDs, corresponding to seven input alarm contacts, while the eighth output is provided for the buzzer. (The buzzer can be replaced with a hooter using additional circuitry.)

All alarm inputs are designed for NO contacts. Apart from digital pin 2 through pin 13 of Arduino, analogue pin A0 through pin A5 are also used as digital I/O pins to monitor the seven different input conditions.


You can read up to 3 premium stories before you subscribe to Magzter GOLD

Log in, if you are already a subscriber


Get unlimited access to thousands of curated premium stories, newspapers and 5,000+ magazines


August 2019