CDI unit testing on multimeter. Motorcycle ignition system. capacitor discharge. CDI unit wiring pin

In video CDI unit testing on multimeter. Motorcycle ignition system. capacitor discharge. CDI unit wiring pin you will get knowledge about motorcycle very important part which is known as cdi unit. CDI units as the most commonly failing parts for many motorcycle brands. The ignition system is the most important system for any vehicle to make it runing. The ignition system is responsible to produce a spark in a petrol or gas engine. If spark is not provided in a petrol engine, the engine would not start or run. There are four very important parameters for a petrol engine to make it work. Fuel, spark, compression and timing. if anyone of these will be missing, the engine wouldn't start. The ignition system consists of a charging coil, pulse coil, ignition coil, kill switch, spark plug and cdi unit. CDI unitis is an electronics module inside which is a capacitor that is charged and discharged to produce a spark for the gas engine. The capacitor discharge timing or ignition timing is provided by the pulse coil. The capacitor inside the cdi is charged at high voltage of around 400v DC. 400v as is generated by motorcycle or motorbike alternator or charging coil which is converted into DC inside the cdi unit. The pulser coil produces a triggering signal of about 4V to trigger the cdi unit.

What is a Capacitor Discharge Ignition (CDI) & Its Working
At present, many things have been changed because of technology. The researchers invented the CDI (Capacitive Discharge Ignition) system for SI (Spark Ignition) Engine using electronic ignition & contact point ignition. This system includes a pulse control circuit, spark plug, pulse generation circuit, main charge & discharge capacitor coil, etc. There are different types of ignition systems where different classic ignition systems are developed to use in different applications. These ignition systems are developed using two groups like CDI (Capacitor Discharge Ignition) systems as well as IDI (Inductive Discharge Ignition) systems.
What is a Capacitor Discharge Ignition System?
The short form of the Capacitor discharge ignition is CDI which is also known as thyristor ignition. It is one kind of automotive electronic ignition system, used in motorcycles, outboard motors, chainsaws, lawnmowers, turbine-powered aircraft, small engines, etc. It was mainly developed to conquer the long charging times which are connected through high inductance coils employed for IDI (inductive discharge ignition) systems to make the ignition system more appropriate for high engine speeds. The CDI utilizes capacitor discharge current toward the coil for firing the spark plugs.
A Capacitor Discharge Ignition or CDI is an electronic ignition device that stores an electrical charge and then discharges it through an ignition coil in order to produce a powerful spark from the spark plugs in a petrol engine. Here the ignition is provided by the capacitor charge. The capacitor simply charges and discharges within a fraction of time making it possible to create sparks CDIs are commonly found on motorbikes and scooters.
Capacitor Discharge Ignition Module
The typical CDI module includes different circuits like charging & triggering, a mini transformer & the main capacitor. The system voltage can be increased from 250V to 600V through a power supply in this module. After that, the flow of electric current will be there toward the charging circuit so that capacitor can be charged.

The rectifier within the charging circuit can avoid the discharge of the capacitor before the ignition moment. Once the triggering circuit gets the triggering signal, then this circuit will stop the working of the charging circuit & allows the capacitor for discharging its o/p fast toward the ignition coil of low inductance.
In Capacitor discharge ignition, the coil works like a pulse transformer rather than an energy storage medium because it does within an inductive system. The o/p of the voltage toward the spark plugs is extremely reliant on the CDI design.

The insulation capacities of voltages will exceed the existing ignition components which can cause components failure. Most of the CDI systems are designed to provide extremely high o/p voltages however this is not constantly helpful. Once there is no signal for triggering then the charging circuit can be re-connected for charging the capacitor.




Working Principle of a CDI System
A capacitor discharge ignition works by passing an electrical current over a capacitor. This type of ignition builds up a charge quickly. A CDI ignition starts by generating a charge and storing it up before sending it out to the spark plug in order to ignite the engine.

This power passes through a capacitor and is transferred to an ignition coil that helps boost the power by acting as a transformer and allowing the energy to pass through it instead of catching any of it.