Despite its simplicity, the Battery Low Voltage Alarm circuit has a very important function. It forewarns you of approaching battery failure so that you may run to the store and get replacement cells before your equipment stops functioning entirely. Because of its compact size and low current need, it may be integrated into the devices […]
Security and Alarm
AC 220V Over Current Monitor and Cut OFF Circuit
The proposed AC mains 220 V load over current cut off circuit continuously monitors the current flowing through a connected load. If this current increases beyond a certain preset level, the circuit trips the relay and disconnects the load from the AC. Basic Working This 220 V over current cut off circuit is indeed subject […]
Shock Vibration Detector Circuit using 801S Sensor
The shock alarm module that we are presenting to you can be used in a house as well as in a car. Given its low manufacturing cost, it can be replicated in several copies and connected to different positions at home. It can be also installed in a vehicle where it will trigger a siren […]
Child Crying Monitor Circuit using Power Line Communication
In this child crying monitor circuit when the baby wakes up in their room, the parents are immediately notified, even if they are in another room of their home. A sensor detects the crying sound accompanying the wake-up. After appropriate processing, it sends a signal through the 220V power lines. The receiver, connected to any […]
Ultrasonic Burglar Alarm Circuit
An ultrasonic burglar alarm circuit is an electronic device which transmits ultrasonic waves to detect the movement of an intruding person. The ultrasonic waves hit the intruder and the reflected waves are picked up by the circuit. This reflected wave is used to activate a loud alarm which alerts the owner about the presence of […]
Monitoring 220V AC Load Current using Current Transformer [Circuit Diagram]
In this post I have explained a circuit which can be used for monitoring or controlling AC 220V load current by sensing the load current through a contactless current transformer. Figure 1 below depicts a circuit diagram designed for a non contact load current sensing through a current transformer, which seemed to work well. It is […]