 Hello students, today we are going to discuss automobile starting and charging system. I am Mr. Narthambhake, assistant professor, Department of Mechanical Engineering, Walsh and the Stop Technology, Sholap. Learning outcome, at the end of this session students will be able to explain automobile starting and charging system. In this particular session, we are going to discuss introduction of starting system, starting system circuit diagram, introduction of ignition system, ignition circuit diagram. Dear students, first of all we will think what is a starting system. Here we will see what is a starting system. The starting system converts electrical energy from the batteries into mechanical energy. To turn the engine over, a malfunction within the starting system will make it difficult to get the engine running. In order to properly service the starting system, you need to understand how it operates. The starting system has five main components. First one is the ignition switch or that is also called as the start button, a neutral safety switch, an option on some vehicles, the starter solenoid, the starter motor and the batteries. This is what the schematic diagram of starting system circuit in which there is a battery and there is a neutral safety switch is there, then ignition switch or starting button is there, magnetic switch is there, starter solenoid is there and the starter motor is there. Here whatever the starter solenoid is there, when the current passes from battery to the starter solenoid, then due to electromagnetic force. Whatever the fork is there, that fork is going to attract towards the starter solenoid and whatever the motor is there, starting motor is there, that is going to engage with the engine of the automobile and then the vehicle is going to start. So for that purpose, you have to turn the ignition switch, that time the current from the battery that is directly passed towards the starter solenoid and then the starter motor is going to start and that passes that particular rotation to the engine and the engine is going to start. So likewise, the starting system circuit is designed. Now we will see how it works exactly, when the key is turned in the ignition switch to the start position or the start button is pushed, electricity flows from the battery to the starter solenoid as we have discussed. Some vehicles are equipped with a neutral safety switch. If the vehicle is in gear when the key is turned, the neutral safety switch blocks the signal to the batteries. So the engine does not start cranking, otherwise the vehicle could jump forward or backward when the key is turned. The starter solenoid is an electromagnetic switch mounted on the starter motor. When coils inside the solenoid are energized by electricity, they create a magnetic field which attracts and pulls a plunger. Attached to one end of the plunger is a sharp lever. The lever is connected to the drive pinion and clutch assembly of the starter motor. The starter motor is a small but powerful electric motor that delivers a higher degree of power for a short period of time. When the starter motor is energized, it engages the flywheel ring gear and produces torque which turns the flywheel and cranks the engine. When the driver releases the ignition switch from the start position to the run position, the solenoid is deactivated. Its internal return spins cause the drive pinion to be pulled out of mesh with the flywheel and the starter motor stops and vehicle engine is continuously running with the help of initial starting. And furthermore, when you apply the gear, that time vehicle will run from its initial position. So likewise, the starting system circuit is working. Next one is the charging system. The charging system is an important part of the electrical system. It provides electrical current for the lights, for the radios, for the heaters, for the engines and for the electrical system and other electrical accessories. It also maintains the batteries in a charged state, recharging them as necessary. In order to properly service the charging system, we need to understand how it operates. The charging system has three main components. One is alternator, second one is voltage regulator and third one is the battery. We can see that three parts over here, how that are connected. The alternator is connected to the voltage regulator, the battery is located and other whatever the negative terminal of the battery is there, that is earth to some of the part. Positive terminal of the battery is connected to the alternator and positive terminal of the alternator is connected to voltage regulator again. And negative terminal of the battery is again grounded. So likewise the charging system circuit of this particular automobile electric system is designed. Now how it works? So the alternator generates electrical power to run accessories and to recharge the batteries. It is normally driven by a belt located off the crankshaft. Mechanical energy from the crankshaft is converted by the alternator into electrical energy for the batteries and accessories. The voltage regulator acts as an electrical traffic cop. To control alternator output it senses when the batteries needs recharging or when the vehicle's electrical needs to increase and adjust the alternator's outputs accordingly. The batteries are the reservoirs of chemical electrical power. Their primary purpose is to crank the engine. They also supply power to the vehicle accessories when the electrical load is too great for the alternators. And also whatever this particular charged energy is there that we are utilizing for different lightning system that we have seen earlier. Then for the ignition system then for the AC that is also called air conditioning and for different side indicator light. So likewise we are using this particular electricity or the power of the battery for different applications in the automobile. So these are the references. So once that is the Bloom's taxonomy level that the level that we are achieving over here. Pripalsing automobile engineering that is the book by Standard Publisher, automobile mechanics by N.K. Geary, automobile electrical equipment by P. S. Cowley, then Newton and Schiltz and T.K. Garrett by that is the book name is Motor Vehicle by Elsewhere Publications. The book name is Automotive Mechanics by Tata McGraw-Hill Publishing House. Thank you. Thank you.