Project - Analysis of a practical automotive wiring circuit
1)MAJOR COMPONENTS:
Battery,starter,ammeter,ignition coil,distributor,breaker,Distributor,current and voltage regulator.
2)BATTERY:
A battery is a device that stores chemical energy and converts it to electrical energy. The chemical reactions in a battery involve the flow of electrons from one material (electrode) to another, through an external circuit. The flow of electrons provides an electric current that can be used to do work.
The chemical reactions in the battery causes a build up of electrons at the anode. This results in an electrical difference between the anode and the cathode. You can think of this difference as an unstable build-up of the electrons. The electrons wants to rearrange themselves to get rid of this difference. But they do this in a certain way. Electrons repel each other and try to go to a place with fewer electrons.
In a battery, the only place to go is to the cathode. But, the electrolyte keeps the electrons from going straight from the anode to the cathode within the battery. When the circuit is closed (a wire connects the cathode and the anode) the electrons will be able to get to the cathode. In the picture above, the electrons go through the wire, lighting the light bulb along the way. This is one way of describing how electrical potential causes electrons to flow through the circuit.
However, these electrochemical processes change the chemicals in anode and cathode to make them stop supplying electrons. So there is a limited amount of power available in a battery.
When you recharge a battery, you change the direction of the flow of electrons using another power source, such as solar panels. The electrochemical processes happen in reverse, and the anode and cathode are restored to their original state and can again provide full power.
IGNITION COIL DISTRIBUTOR:
The working of the ignition distributor is simple. When the distributor shaft began to rotate, it also rotates the cam and rotor of the distributor. While the cam rotates it pushes the cam follower that is connected to the contact breaker.
A distributor is defined as an enclosed rotating device that is used in IC engines with mechanically timed ignition.
In the magneto system and many modern computer-controlled engines, the distributor has a mechanical or inductive breaker switch to open and close the primary circuit of the ignition coil.
The main function of the car distributor is to provide the high voltage current produced by the secondary coil to the correct spark plugs in the correct firing order and at the correct time. Now let’s see what are the parts of a distributor.
The contact points of the contact breaker suddenly open and close the primary current through the primary winding. This action produces the high voltage of current in the secondary winding.
The high voltage current is transferred to the central terminal of the current distributor. This current from the central terminal then travels through the carbon brush to the outer edges of the rotor.
Finally, as the rotor makes contact with the internal terminal of the spark plug in the distributor cap, a high voltage electrical pulse travels to the spark plug and gives a spark within the cylinder head.
In this way, the distributor generates a spark in each spark plug in the correct order and at the right time.
CURRENT AND VOLTAGE REGULATOR:
Just like situations in which we need to regulate the voltage in our designs, there are scenarios where we need to regulate the current that’s being supplied to a particular part of our circuit. Unlike transforming (changing from one voltage level to another) which is usually one of the major reason for voltage regulations, current regulation is usually about keeping the current that’s being supplied constant, irrespective of variations in load resistance or input voltage. The circuits (integrated or not) which are used to achieve constant current supply are called (Constant) Current Regulators and they are very commonly used in power electronics.
While Current regulators have been featured in several applications over the years they are arguably not one of the most popular topics in electronics design conversations until recently. Current Regulators have now achieved a sort of ubiquitous status due to their important applications in LED Lighting among other applications.
The operation of a current regulator is similar to that of the voltage regulator with the major difference being the parameter they regulate and the quantity they vary to supply their output. In voltage regulators, the current is varied to achieve the required voltage level, while current regulators usually involve variations in voltage/resistance to achieve the required current output. As such, while it is possible, it is usually difficult to regulate voltage and current at the same time in a circuit.
3)If the total load of a battery is 10A and the cable size is 25A then the fuse rate should lie somewhere between these values,for example the fuse rate should be 15A to allow normal flow and blow on an overload.
4)If the load is 500W I would recommend 14 amp hours at 36 volts or 10.5 amp hours at 48 volt battery.
5)In this above given diagram the generator and distributor are connected in parallel in order to achieve the achieve the same amount of voltage flowing through them.
6)In the above given diagram the battery and the starter are connected in series to inorder to achieve the same amount of current flowing through them.