Posted in Ignition Wires – Ignition Coil Classification

Patronage: Janmor. For more than a hundred years, the design of internal combustion engines with spark ignition has undergone tremendous changes. This also affected the ignition systems, but the principle of operation and the main components remained the same.

Posted in Ignition Wires

Patronage: Janmore

It should include a spark plug, a coil, and a device that turns power to the coil on and off. So let's take a look at the changes that have taken place in coil design. To do this, the coils found in different types of vehicles must be classified. According to the method of dividing high voltage into individual cylinders, coils can be divided into three groups:

Single-pole coil coupled to the ignition distributor

This is the oldest but still quite common solution. One end of the primary winding is connected to the voltage switching system (circuit breaker, electronic module, motor controller), and the other end to the secondary winding. The terminal common to both windings is connected to the ignition switch. The other end of the secondary winding is connected to the spark plug. In this solution, one coil serves all cylinders. The exception is the historic solution used in Syrena or Wartburg vehicles. There, each of the coils served one cylinder, but their arrangement was the same as in the case of a coil interacting with the distributor. Unipolar coils can be available with a built-in power booster for the ignition system (a solution often found in the VAG group, an example of a Janmor reference is JM5046).

Bipolar coil

This decision made it possible to eliminate the ignition distributor. Its characteristic feature is the lack of connection between the primary and secondary windings. Both ends of the secondary winding are connected to two spark plugs. The ignition spark jumps on them at the same time - on one it ignites the mixture at the end of the compression stroke, and on the other it appears at the end of the exhaust stroke and is “lost”. As you can easily see, this solution can be used for engines with an even number of cylinders. Most often, this is a set of two or three double coils mounted in one housing. An example of a Janmor reference is JM5097 for a six-cylinder engine used in Opel (Vectra, Omega) vehicles.

Single pole individual coil

This is the latest solution that is increasingly being used by automakers. Here, too, there is no connection between the primary and secondary windings. One end of the secondary winding is grounded and the other end is directly connected to the spark plug. This decision made it possible to eliminate the ignition wires and make it easier for the controller to control the ignition of the mixture. It also allows you to individually adjust the ignition timing in each cylinder. An example of a Janmor reference is the JM 5008 coil used in Renault vehicles. Separate single-pole coils can also be made in the form of a single block connecting them in a common housing. The unit may also include power amplifiers to control the voltage applied to the primary windings. An example of such a solution is the ODM 253 coil used in Opel three-cylinder engines.

Three trends

By observing changes in the way high voltage is distributed, we can see three main trends. The first is to exclude completely emergency ignition distributors (push-pull coils), the second - rejection of high-voltage cables (individual coils). The third trend concerns the installation of additional elements in the form of power amplifiers along with the coils. All these changes are designed to reduce the risk of punctures and create additional diagnostic capabilities. The disadvantage of these solutions is the higher cost of a component that must be replaced if one of its components fails. When discussing individual solutions, we provided examples of Janmor SKUs.

Janmor offers a very wide range of reels, both simple and advanced. Currently, there are about 300 links. They are distinguished by OEM quality and affordable price. The warranty for selected models is 2, 3 or 5 years.