Project - Analysis of a practical automotive wiring circuit

1. Battery, Starter, Ignition Coil, Generator, Breaker, Distributor, Current & Voltage Regulator, Ammeter, Foot selection switch, Fuse

2. Distributor - It is an enclosed rotating switch used in spark ignition IC engines that have mechanically timed for ignition. Its main function is to provide high voltage current from ignition coil to spark plug in desired firing order.

Main parts of a distributor is Distributor cap, Rotor, Contact Breaker, Distributor Shaft, Cam, Capacitor, Spark advance mechanism.

Working - As the distributor shaft rotates, it rotates the cam & rotor. When the cam pushes the cam follower of contact breaker, the contact points of the contact breaker opens and collapses the primary current through primary winding. This produces high voltage current in the secondary winding. The high voltage current produced is transfer of the distributors central terminal. The current from this terminal reaches outer edge of rotor through carbon brush. As the rotor comes in front of the internal terminal of spark plug in the distributor cap the high voltage pulse pass to plug and produces a spark in cylinder head. The distributor prodeces spark in each plug at the desired time.

Battery - It is used to store energy. It consisit of one or more cells. Converts chemical energy to electrical energy.

Main Parts - Anode, Cathode, Electrolyte.

Working - Electro-Chemical reaction.

Once anode (-ive charge) & cathode (+ive charge) are dipped in the desired electrolyte solution anode gets oxidised and releases electrons and cathode gets reduced and attracts electrons. Thus electron flow occurs and electricity is produced.

Type - 1, Primary battery - Can be used only for one discharge. Not able to charge again and use it.

Eg :- Alkaline battery.

2,Secondary batery - Can be charged once it gets dicharged muliple times.

Eg :- lead acid battery, lithiumion battery.

Starter - In IC engines it is used to give initial power to engine which then continually operates on its own. It is montrd on engine gearbox and meets flywheel teeth.

Main Parts - Armature, Brushes, Commutator, Solenoid, Plunger, Lever, Fork, Pinion, Field coils.

Working - When ignition key pressed or turnrd on the batteryvoltage goes through the starter control circuit which activates solenoid. Which helpsto push the starter gear forward which is messed with engine flywheel. This flywheel is fixed at one end of the crank shaft. Whwn the engine starts the starter disengages from the flywheel.

Types - Direct drive starter motor, Planetary Gear, Permanent magnet gear reduction, Permanent magnet direct drive, Off-set gear reduction, Inertial starter.

3, Current, I = 10A

Normally the fuse rating will be 125 % of the input current. The fuse rating should be as close as the input current so that any hike in the current should burn the fuse and protect the wiring and other equipments.

Fuse rating = 10 * 125% = 12.5 A

4, Power, P = 500 W

Voltage, V = 12 V

Current, I = ?

P = V * I

I = P / V = 500/12 = 41.6 A

Lets take, Time, T = 1 Hr

Capacity = I * T = 41.6 * 1 = 41.6 Ah

5, Many elements are connected in parallel. Two elemets we considering are plate light & tail stop.

They are connected in parallel because each element will have same voltage across it equal to the voltage across the network. While the current through the network is the sum of current through each component.

6, Many elements are coonected in series. Two elements we considering are ignition coil and starter.

They are connected in series because each element will have same current through it which is equal to the current through the the network. While voltage across the network will be equal to sum of the voltage across each component.