• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.


Not open for further replies.
i got a circuit which detect earth fault, i.e if earthing is provided or not. it indicates fault using LED. Now i want to use this circuit with arduino so that i can send alert remotely using gsm. not getting any idea how to proceed. below is the link---
Earth Fault Detector


Well-Known Member
Most Helpful Member
Just replace the indicator LED [LED1] with an opto isolator. The transistor in that will be switched on with 50Hz pulses any time the LED would have illuminated.

However, note that it's a rather primitive circuit and will only sense an earth disconnection if that causes a difference in voltage between neutral and earth. That's quite possible but in no way guaranteed.

Note that R1 will get hot, it definitely needs to be a 1W or possibly 2W resistor; it's average dissipation is about 0.7W so rather dependant on construction and airflow as to what's actually required for safety.
Not open for further replies.

EE World Online Articles