ENGINE IGNITION SYSTEM

IGNITION SYSTEMS REQUIREMENTS: 1. All ignition systems must deliver a high tension spark to each cylinder of the engine in firing order at pre-determined number of degrees ahead of the top dead centre position of the piston. 2. The voltage output of the system must be such that the spark will jump the gap in the spark plug under all operating conditions.

IGNITION SYSTEMS CLASSIFICATION: 1. Single ignition system (consisting of one magneto and necessary wiring) 2. Dual ignition system (consisting of 2 magneto and necessary wiring)

IGNITION SYSTEMS CLASSIFICATION: 1. Single ignition system (consisting of one magneto and necessary wiring) 2. Dual ignition system (consisting of 2 magneto and necessary wiring)

IGNITION SYSTEMS Types: 1. Battery ignition system 2. Magneto ignition system

BATTERY IGNITION SYSTEM

BATTERY IGNITION SYSTEM source of energy is a battery or generator rather than a magneto. A cam driven by the engine opens a set of points to interrupt the flow of current in a primary circuit. The resulting collapsing magnetic field induces a high voltage in the secondary of the ignition coil, which is directed by a distributor to the proper cylinder. How Electronic Ignition System Works - YouTube.MP4

MAGNETO IGNITION SYSTEM The magneto the special type of engine driven AC generator uses a permanent magnet as a source of energy. The magneto develops the high voltage which forces a spark to jump across the spark plug gap in each cylinder. Magneto operation is timed to the engine so that a spark occurs only when the piston is on the proper stroke. Magneto ignition system - YouTube.MP4

MAGNETO IGNITION SYSTEM Types: 1. High Tension Magneto System 2.Low Tension Magneto System

High Tension Magneto System (a) Magnetic circuit (b) Primary electrical circuit (c) Secondary electrical circuit

High Tension Magneto System MAGNETIC CIRCUIT: The magnetic circuit consists of a permanent multi pole rotating magnet a soft iron core and pole shoes. The magnet is geared to the aircraft engine and rotates in the gap between two pole shoes to furnish the magnetic lines of force (flux) necessary to produce an electrical voltage. The poles of the magnet are arranged in alternate polarity so that the flux can pass out of the North Pole through the coil core and back to the south pole of the magnet.

Magnetic circuit

PRIMARY & SECONDARY ELECTRICAL CIRCUIT

PRIMARY & SECONDARY ELECTRICAL CIRCUIT The primary electrical circuit consists of a set of breaker contact points, a condenser and an insulated coil. The coil is made up of a few turns of heavy copper wire, one end of which is grounded to the coil core and the other end to the ungrounded side of the breaker points. The primary circuit is complete only when the ungrounded breaker point contacts the grounded breaker point. The third unit in the circuit is the condenser. It is wired in parallel with the breaker points. The condenser prevents arcing at the points and the circuit is opened, hastens the collapse of the magnetic field about the primary coil.

LOW TENSION MAGNETO SYSTEM

LOW TENSION MAGNETO SYSTEM It delivers current at a low voltage by means of rotation of armature, wound with only one coil, in the field of a permanent magnet. This low voltage current must be transformed to a high tension (high voltage) current by a transformer at or near to the spark plug.

DUAL MAGNETO IGNITION An arrangement in which two magneto fires at the same cylinder or approximately the same time through two sets of spark plugs is known as a double or dual magneto ignition system. Advantages: 1. If one magneto fails, then the other magneto produces current for the ignition system. 2. Two sparks at different part of the cylinders simultaneously provides quicker and complete combustion of air/fuel mixture.

STARTING SYSTEM Starter is a mechanism capable of developing large amounts of mechanical energy that can be applied to an engine, causing to rotate. Piston engine starting system: 1. Cartridge starter 2. Hand inertia starter 3. Electric starter 4. Combination inertia starter 5. Direct cranking electric starter

STARTING SYSTEM Starter is a mechanism capable of developing large amounts of mechanical energy that can be applied to an engine, causing to rotate. Piston engine starting system: 1. Cartridge starter 2. Hand inertia starter 3. Electric starter 4. Combination inertia starter 5. Direct cranking electric starter

STARTING SYSTEM INERTIA STARTERS: The operation of all types of inertia starters depends on the kinetic energy stored in a rapidly rotating flywheel for cranking ability.

STARTING SYSTEM

STARTING SYSTEM DIRECT CRANKING STARTERS: The direct cranking electric starter consist of An electric motor, Reduction gears, and An automatic engaging and disengaging mechanism (torque over load release clutch)