Project - Analysis of a practical automotive wiring circuit

Aim: To identify each of the major elements in the diagram, explaining the purpose and working, calculate the the fuse rating, calculate the voltage and capacity of he battery and to identify any two elements in parallel and series with the reasons for the particular arrangment.

Governing equations:

1. Voltage(V) = Current(I) * Resisstance(R)
2. Power(P) = Voltage * Current (in Watts or kW)
3. Energy(E) = Power(P) * Time(T) (Watt hours)
4. Capacity = I * Time Ah

Objective of the project:

1. Identfication of the all major components.
2. Explaining the purpose and working of three elements.
3. Calculation of the fuse rating for total load of 10 A.
4. Voltage and capacity of the battery for 500W.
5. Identifining two elents in parallel and two elements in series and explaing the reasons for there respective arrangement.

Body of the content:

1. Identify the major components?
   1. Battery
   2. Starter
   3. Ignition coil
   4. Distributer
   5. Breaker
   6. Ammeter
   7. Generator
   8. Foot selection switch
   9. Current and Voltage regulator
   10. Fuse
   11. Scaled lamp
   12. parking lamp
   13. Horn
   14. Gas tank unit
   15. Dome light switch
2. Explain the three components in the diagram.
   1. Generator: The generator is a device which converts the mechanical power to electrical power. The output shaft is connected to the Generator using the belt and pulley system. Generator consists of the two parts Stater and Rotor. The stater comprises of the static coil would in a particular pattern whose terminals supply the electricity. Rotor consists of the strong magnet/exited coil which rotates and cuts the flux and sets motion the electrons (current).

   2. Ignition coil: The purpose of the ignition coil is to produce very high voltage (50000 Volts) from a low voltage source (Battery 24/12 volts). It is mainly used in the petrol automobiles. The working of the ignition coil is same as the transformer both work on the concept of electromagnetic induction, were oscillating electric current induces magnetic field. Here the primary coil has very less number of turns compared to the secondary coil. When the primary coil is excited with AC current (makes and breaks the flow also) the primary coil induces the magnetic field which Induces the electric current in the secondary coil due to the breaking and making flow a very high electric voltage is generated this high voltage applied across the spark plug in the combustion chamber with the help of distributer to ignite the fuel in the combustion chamber.

   3. Fuse: Fuse is the safety device connected in series, used to cut/break the circuit if the current flowing is higher than the rated norms to prevent the damage to the system components. The fuse works on the principle of heating effect caused by the current. It consists of a thin wire which has melting point very specific for rated current range (to the corresponding resistance value of the rated current). The fuse gets heated up by the resistance caused by the higher current values (Ohms law) and as the melting point of the fuse wire is low and very temperature specific the fuse wire melts off and opens the circuit and prevents the damage to the component of the circuit.
3. Calculation of the fuse rating:
   • Calculation of the fuse rating:
     1. First method:
        • For the purpose of the initial surge occurrence when the components are switched on for the first time the fuse need to have 25% higher current handling capacity to perform correctly and withstand the surge:
        • To calculate this we know the total load i.e. 10 Amps, so 25%-50% higher means 12.5Amps.
        • The fuse rating of 12.5 Amps to 15 Amps is required.
     2. Second method:
        • Current (I) (Total load) = 10 Amps.
        • Voltage (V) = 24 volts.
        • Power (P) = V*I = 24*10 = 240 Watts.
        • Fuse rating = Fr = (P*1.5)/V = (240*1.5)/24 = 15Amps.
   • The fuse rating is 25% higher than the highest current flowing, this kept on purpose because when the circuits are closed initially there is current and voltage surge, in this case the current goes higher than normal operating values, to avoid circuit break due to this condition the fuse rating kept in between the rated operating current and the highest current possible without any damage to the components.
4. Calculate the voltage and capacity of battery for load of 500Watts:
   1. Power = 500W
   2. Power = VI
      • Voltage = Power/I = 500/10 = 50 Amps.
   3. Cpacity of the battery:
      • Capacity = I * Time = 10 *1 = 10 Amp-hr
5. Identify any two elements which are connected parallel to each other. Why they are connected in parallel?
   • Head light:
     • The head light are connected in parallel because if they are connected in series the current flow is same but the voltage is depleted for every resistor which causes drop in emitted light. Another main reason is if they are connected in series and if one gets damaged others will not work as the circuit is open, to avoid this all the lights are connected in parallel.
   • Horn:
     • Horns should be connected in parallel to ensure that biith of them recieves 12Volts.
     • Incase it is connected in series the voltage is droped and horns may malfunction.
     • Horns are connected in series because if one fails the other will remain functional.
6. Identify any two elements which are connected in series. Why they are connected in series?
   • Ammeter: It is device used to measure the amount of current flowing through the conductor/circuit. Ammeter is a connected in series because it is used to measure the current passing through a wire (not the total available voltage), as it is connected in series the current passes through it and measures current else if the ammeter is connected in the parallel form it will pass all the current to the neutral wire without any current going to the circuit because of its very low resistance and it will calculate the total available current flow not the current flowing in the circuit.
   • Battery: It is a device which converts the chemical energy directly into the electrical energy by electrochemical reactions. The battery is connected in series to the circuit because the current needs to flow from one point of the circuit to another point of the circuit to make the circuit functional and it is only possible by adding the battery in series with the circuit. (As battery contains both the terminals (positive and negative) these terminals must be connected the electrons flows from one terminal to another terminal, this is accompanied by the current flowing from)

Results:

1. The components are identified and the purpose of three elements are explained.
2. The fuse rating is calculated as 12.5-15A.
3. The voltage and capacity of the battery is 50V and 10Ah.
4. The elements connected in series and parallel are mentioned and the purpose respective arrangment is explained.

Conclusions:

1. The online diagram is studied.
2. The elements are identified and explained.
3. The fuse rating is calculated.
4. The voltage and the capacity of the battery are calculated.
5. The arrrangment of the elements in series and parallel are explained.