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EDC Control System

The electronic control system for EDC diesel Common Rail system includes three large:

1. Sensors to register the operating mode that convert various physical parameters into electrical signals.
2. ECU to generate electrical output signals based on signals from the sensors and a predetermined algorithm.
3. Drives for converting the output electrical signals the ECU mechanical parameters.

Sensor Engine speed

1 - the permanent magnet 2 - housing 3 - crankcase	4 - a metal rod 5 - reel 6 - toothed rotor

The position of the piston in the cylinder is critical in determining the fuel injection timing into the combustion chamber. Since the pistons through connecting rods rigidly connected to the crankshaft, the crankshaft position sensor control unit transmits information about the position of the pistons. Inductive sensor for the angular velocity determines the speed of the crankshaft, and the important input variable is passed ECU.

The ferromagnetic rotor 60 teeth mounted on the crankshaft, thus the rotor 2 missing tooth. This interval is set in a certain position relative to the crankshaft and the position of the piston in the first cylinder. The sensor is a permanent magnet and a metal rod with an inductive coil. With the passage near the pole teeth of the sensor rotor it induced a sinusoidal voltage whose amplitude increases with increasing engine speed.

Camshaft position sensor

The camshaft operates intake and exhaust valves and rotates at half crankshaft speed. When the piston moves toward the top dead center position of the camshaft indicates which piston is in the compression stroke or the exhaust stroke.

Camshaft position sensor operates on the Hall effect. Short sensor informs ECU, which passed the first cylinder on the compression stroke.

Temperature sensors

1 - Connector 2 - housing 3 - NTC resistor

Temperature sensors are installed at various locations of the engine and designed to measure the temperature of the coolant air entering the engine, engine oil and returning fuel to the fuel tank. The basis of each sensor is a resistor whose resistance varies with temperature with a negative temperature coefficient (NTC). The voltage drop across the resistor through an analog-digital converter (ADC) is transmitted ECU. Characteristics of the sensor is recorded in the ECU memory as a function of voltage.

Characteristics of the temperature sensor (NTC)

Airflow Meter

1 - the connector pins 2 - internal connections 3 - electronic control unit 4 - an air inlet	5 - the sensor element 6 - an air outlet 7 - housing

A fuel injection system designed for precise metering of fuel depending on the amount of inlet air at various engine operating modes. The proper ratio of air and fuel is required to reduce the amount of harmful substances in the exhaust gases. This requires the use of sensors that accurately capture the actual flow of air entering the engine cylinders at each moment.

The accuracy of the sensor must not depend on the pulsations of the exhaust gas recirculation and the temperature of air entering the engine. These requirements correspond to the air flow meter heated thin film. Micromechanical measuring system registers the air flow and direction.