Project - Analysis of a practical automotive wiring circuit
Major elements?
Battery, starter, Generator, current and voltage regulator, ignition coil, lights and switches, fuel level sensor and guage, ammeter
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Purpose and working of any 3 elements?
1. Battery : it is to provide starting electric power to crank the engine with the help of a the starter motor. Chemical energy in the battery is converted to electric. Turning the ignition key closes the contactor to the starter which turns the engine drawing power from the battery. Once ignition of the fuel takes place in the engine, the starter motor is stopped.
2. Generator : it is to provide electric power after starting the engine. The mechanical drive (energy) for the DC generator is taken from the engine crankshaft. The copper coils are spinning inside a magnetic feild, which generates an EMF in the coil, which in turn pushes a current supply out of the generator. The supply from the generator is regulated by the current and voltage regulator.
3. Ignition Coil : it provides the voltage necessary to create a spark at the electrodes of the spark plug. The ignition coil is a step up transformer, which boost the voltage by several times to cause a high voltage difference between the electrodes of the spark plug. This high voltage difference causes a spark. And this sparking is timed using a distributor which fires up the combustion process in the different engine cylinders.
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If the total load is 10A, then this is the maximum current through the circuit. So a fuse of 10A can be used.
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500W load operating in a 12V circuit will draw a current of 41.6 Amps (Power=Voltage*Current)
So a 12V, 50AH (greater than 41.6) with C-rating of 1, if the load has to be supplied for less than 1 hour.
A 12V, 25AH with a C-rating of 2 can also be used if the load is connected only for a short time.
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Both the Headlights are connected in parallel, as we need to turn both of them ON at the same time for good visibility.
The battery and the generator are in parallel, as we need supply from any one of them at a time.
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All light switches to their corresponding lights will be in series, to control the light ON/OFF from the switch.
Ammeter will always be is series to the either of the power supply (from battery or generator). This allows for current measurement.
Fuel guage to the gas tank unit is in series, to determine the current passing through the gas tank unit (sensor) and display the fuel level in the tank for the operator.