Contents: Method of measurement ⤓ Oscillogram of voltage of a working…⤓ Characteristic sections of the…⤓
Method of measurement
Install a special sensor on the high-voltage wire.
Attention! For cylinders 2 and 4, the polarity of the breakdown voltage will be opposite to the polarity of the voltage for cylinders 1 and 3.
Since the ignition system with simultaneous spark discharge in two cylinders is used, it is possible to simultaneously observe voltage oscillograms for two cylinders (for 1 and 4 cyl. and for 2 and 3 cyl.). However, it is possible to take a high voltage oscillogram only for the cylinder on whose wire a special sensor is installed.
It can be difficult to determine which cylinder the observed oscillogram refers to. It should be remembered that the oscillogram of the cylinder to which the high-voltage sensor is connected will have a more stable image on the screen.
Install a synchronization sensor on the high-voltage wire.
Attention! Install the synchronization sensor on the same high-voltage wire on which the special high-voltage sensor is installed.
Oscillogram of voltage of a working ignition system
- Conditions under which the measurement is performed (only the parameter "pattern selector" – image type – has been changed)
- Pattern selector (image type)
- Display (long display)
Conditions under which the measurement is performed
Characteristic sections of the oscillogram
Section A: the amplitude (height), duration and trailing edge of the spark discharge allow us to establish the following deviations (See examples of oscillograms with typical faults – examples 1, 2, 3 and 4).
Plot A
Section B: number of oscillations in the attenuation section (See example of oscillograms No.5).
Plot B
Section C: number of oscillations at the beginning of the section of breakdown voltage growth (See example of oscillograms No.5).
Plot C
Point D: breakdown voltage (as well as voltage distribution across the cylinders) allows us to establish the following patterns.
Point D
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