Introduction: Noise Making AC Current Sensor

Picture of Noise Making AC Current Sensor

Here is the simple AC Current Sensor. It is useful for checking the power in mains wiring especially the broken points in concealed wiring. Whenever the probe gets close to AC Mains the LED Glows and buzzer beeps. It can detect the line from a distance of upto 31 cm.

Step 1: Gather Materials

Picture of Gather Materials

1. LED

2. Buzzer

3. BC558

4. 100 ohm resistor

5. 22uF Capacitor

6. BC549 Transistor

7. 10k Resistor

8. 12k Resistor


10. 100k Resistor

11. Telescopic Antenna

Step 2: Create the Circuit

Picture of Create the Circuit

The circuit uses an n-channel FET BFW11 for detecting the mains voltage.

Assemble the circuit on a general purpose circuit board and use a miniature DC Buzzer with internal oscillator and transparent LED.

Step 3: Antenna

Use 10cm steel rod or a telescopic antenna as the probe.

Now, you are done with your noise making AC Current Sensor.


gm280 (author)2017-01-28

Nice project. Could have used a circuit board and finished product. But it can be build to a lot for different designs and configurations. And even SMD parts would make it really small. With that all stated, I would not totally rely on this to assure there was no power on any line. I would back it up with a quality volt meter myself for a second opinion. JMHO

Patel Darshil (author)gm2802017-01-29

Thanks for the compliment and suggestion.

About This Instructable




Bio: Hello, I am 17 year old innovator living in India. My interest lies in Electronics. Surf through my creations and enjoy!!!!1
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