ROD AS 9T0988 - Caterpillar

Magneto
Illustration 1 g00579844
Cutaway View Of A Fairbanks Morse Solid State Magneto (1) Alternator. (2) Distributor rotor. (3) Capacitor. (4) Coil. (5) Rotor.Ignition power is created in the alternator (1). This alternator consists of a rotor that has eight poles. The alternator also has a stator. The stator has four poles. The alternator has a three-phase full-wave rectified output. This output flows into the main storage capacitor (3). A zener diode is located in the end cap. A capacitor and the zener diode regulate the voltage of the capacitor.The rotor for the trigger (5) is timed to the rotor for the distributor (2). The rotor for the distributor is timed to the engine. The rotation of the rotor for the trigger (5) in the coil (4) will create two properly timed pulses. These pulses are in two coils. The two coils are connected in series. The coils energize the ignition circuit. This is done by discharging a capacitor. This capacitor is discharged through a silicon controlled rectifier SCR switch.The voltage that is generated by the alternator will combine with the voltage that is generated by the coil. This voltage will flow into one circuit. This circuit will ignite all of the cylinders. Distribution of the voltage to the proper cylinder is accomplished by the rotation of the distributor rotor. This distributor rotor operates as a transformer. The distributor rotor does not perform ignition timing. The distributor rotor will select a cylinder. This cylinder should receive the signal for engine ignition. The distributor rotor and the shaft rotate at engine speed. The distributor rotor and the shaft are positioned for the transfer of energy. This energy is transferred from one coil that surrounds the distributor. The correct SCR switch will ignite the correct cylinder spark plug.Magneto
Illustration 2 g00587625
Altronic Magneto (1) Alternator. (2) Electronic firing section.The Altronic magneto is made of a permanent magnet alternator section (1) and electronic firing section (2). There are no brushes or distributor contacts.The engine turns the drive tang for the magneto (7). The drive tang turns alternator (3), speed reduction gears (5) and rotating timer arm (9). The power from the alternator will charge the storage capacitor (8). There are separate pickup coils (6) for each cylinder. There are separate silicon controlled rectifiers SCR (10) for each cylinder. The timer arm passes over pickup coils (6) in sequence. The pickup coils turn on the solid state switches (10). This will release the energy that is stored in capacitor (8). This energy leaves the magneto through the wiring harness. The energy then flows to the ignition coils and the energy is transformed to high voltage. This high voltage is needed to fire the spark plugs.
Illustration 3 g00579848
Cross section of the Altronic solid state magneto (3) Alternator. (4) Vent. (5) Speed reduction gears. (6) Pickup coil. (7) Drive tang. (8) Storage capacitor. (9) Rotating timer arm. (10) SCR solid state switch. (11) Output connector.
Illustration 4 g00647487
(12) Sensor. (13) Air Gap.The Caterpillar digital ignition system is designed to operate from a