PISTON AS 3349982 - Caterpillar

Electronic Ignition System (EIS)
The EIS provides control of the ignition.
Illustration 1 g01157039
Typical view of the G3408C engine (1) Oxygen sensor (2) Oxygen buffer (3) Manifold air pressure sensor (MAPS) (4) Manifold air temperature sensor (5) Electronic ignition system module (EISM) (6) Right hand detonation sensor (RHDS) (7) Transformer (8) Left hand detonation sensor (LHDS) (9) Junction box (10) Emergency stop button (11) Air/Fuel ratio valve (12) Gas regulator
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Front view of the G3408C engine (13) Speed/timing sensor
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Typical view of the G3412C engine (15) Electronic ignition system module (EISM) (16) Right hand detonation sensor (RHDS) (17) Left hand detonation sensor (LHDS) (18) Distribution panel (19) Gas regulator
Illustration 4 g01174503
Front view of the G3412C engine (20) Speed/timing sensor (21) 70 pin connectorEIS Control Module
Control module (5) provides the signals for the ignition transformers.Transformers
There is a transformer (7) underneath the valve cover for each cylinder. The transformers deliver high voltage to the spark plugs.Sensors
The sensors provide signals to the control module. The control module uses the signals in order to provide the signals to the transformers at the appropriate time.Manifold Air Pressure Sensor
The control module uses the signal from inlet manifold pressure sensor (4) in order to determine the engine load.Manifold Air Temperature Sensor
Inlet manifold temperature sensor (4) provides a signal to the EIS that indicates the temperature of the air/fuel mixture in the inlet manifold. The EIS uses the information in order to control the air/fuel ratio.Detonation Sensors
Detonation sensors (6) and (8) produce a voltage signal that is proportional to the level of detonation. The control module uses the signals from the detonation sensors in order to determine the level of detonation. To eliminate detonation, the control module will retard the ignition timing.Speed/Timing Sensor
Speed/timing sensor (13) provides information to the control module about the position of the crankshaft and the engine rpm. The control module uses the information in order to determine the ignition timing.Engine Speed Sensor (Magnetic pickup)
Illustration 5 g01163524
Engine speed sensor (14) provides a signal to the EIS that indicates the speed of the engine. The EIS uses the signal in order to govern the speed of the engine. The speed sensor (magnetic pickup) is installed in the left side of flywheel housing.Actuators
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Electronic throttle actuatorThrottle Actuator
Throttle actuator (15) provides precise control of the speed of the engine. A linkage connects the actuator to the throttle plate.The engine speed is detected by an engine speed sensor (magnetic pickup) that is installed in the flywheel housing. The sensor generates AC voltage that is sent to the governor. The governor sends DC voltage to an actuator. The actuator converts the electrical input into a mechanical output. The actuator moves the linkage that is connected to the throttle plate in order to adjust the engine speed.If the engine speed is greater than the speed setting, the governor reduces the output to the actuator. If the engine speed is less than the speed setting, the governor increases the output to the actuator.The ProAct actuator is an electronic actuator. The throttle plate is driven directly