International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 06 Issue: 09 | Sep 2019 www.irjet.net p-ISSN: 2395-0072 © 2019, IRJET | Impact Factor value: 7.34 | ISO 9001:2008 Certified Journal | Page 347 PASSWORD BASED CIRCUIT BREAKER USING DTMF Mithilesh Padhen 1 , Prof P.V. Sontakke 2 1 Student, Dept. of Electronics and Telecommunication Engineering, Pimpri Chinchwad College of Engineering, Pune, Maharashtra, India 2 Professor, Dept. of Electronics and Telecommunication Engineering, Pimpri Chinchwad College of Engineering, Pune, Maharashtra, India ---------------------------------------------------------------------***---------------------------------------------------------------------- Abstract - Today, in the age of technology and high- end machines working on a live electric line is now considered significantly safer than in years past. The rapid and structured growth of the electrical industry has developed effective standards and established safety procedures to minimize various types of major hazards that led to severe injuries and death of the operators. However, if the scenario of the line needs to repair that’s where the job will be. Understanding various potential dangers of working with very high-voltage equipment is mandatory before going up on any electrical pole or high voltage devices. Given the tremendous challenges and opportunities, the job entails, understanding and learning what could go wrong in the process of implementing is the optimized and safe way to ensure an accident doesn’t occur in the case of electrical circuits. So, in this project, a password-based circuit breaker is designed which is an operated electrical switch which designed to protect an electrical circuit from damage or breakdown caused by excess current from an overload or short circuit, or any other failure. The project having primary function is to interrupt the current flow after a fault is detected. Considering the case of fuse, which generally operates once and then it has be replaced, but a circuit breaker can be reset either manually or automatically according to the working conditions present to resume normal and smooth operation. Key Words: Live Electric line, High-voltage equipment, Circuit breaker, Current flow, Fuse etc. 1. INTRODUCTION The Power system fault is an unwanted condition occurring in the power system. These types of conditions are short circuit, current leakage, ground short, over current and over voltage. The methodology used here is the application of the mobile technology with the electrical circuit. Also, it involves integration of DTMF module with circuit and loads for generating output response of the system, which will eventually produce a very efficient and reliable result. 1.1 Objectives  To study and simulate the circuit using different simulation software.  To interface different components to the microcontroller.  To study the PCB design including coating, etching, drilling etc.  To mount the component with proper soldering.  To test a circuit using breadboard and troubleshoot the same and to generate the report based on the overall system. 1.2 Problem Statement This password-based circuit breaker system using DTMF should provide a solution which ensures the safety of the system of the maintenance staff and provide security. 2. METHODOLOGY 2.1 Block Diagram Fig-1: Block diagram Here the mobile phones are used as the inputs for the systems and the DTMF module decodes the signal and give the output to the microcontroller. Then controller provides input to the relay driver and then relays will work at last the load will be ON or OFF. 2.2 Working Principle DTMF encoder which is generally present in mobiles, and the decoder circuit is present in the microcontroller. The mobile is connected at one end of the circuit with the help of the phone jack. The mobile jack has a presence of two wires. The red wire is connected to the decoder IC and the black one is grounded. Whenever the user tries to make a call to the number in phone, then automatically the call goes into auto answer mode and the frequency of the signal corresponds to key pressed on the phone keypad send by the user is decoded by