Basic concepts of electrical engineering (Focus Turnier 1)

Electric current flows only in a closed electric circuit. Electric circuits consist of a current source (battery, generator), consumers (incandescent lamp, starter, electric motor) and cable bundles consisting of countless wires. Cable bundles create the necessary connections between the current source and the consumer. The basic concept of electrical engineering is explained by our example: imagine a water pipe through which a certain amount of water flows under a certain pressure from A (current source) to B (consumer). The same thing happens in the electric circuits of your Focus. For example, when the light turns on when you open the door.

Voltage: it corresponds to the pressure in the water supply system. The unit of measurement of voltage is volt (V). Current: corresponds to the amount of water that flows through the water supply system in a certain amount of time. The unit of measurement of current is ampere (A).

Power: the product of voltage and current shows how much work the consumer will produce from the electric power of the current source. The unit of measurement of power is watt (W).

Resistance: comparable to a water supply valve. When the valve is open, water flows freely in the pipe (resistance is 0). When the valve is closed, the resistance gradually increases until no water flows at all (resistance ω). The unit of resistance is ohm (Ω).

Wires: comparable to water pipes. The required wire thickness (cross-section) depends on the consumer. The control lamp gets by with a wire thickness of 0.5 mm². The starter needs a cable thickness of 16 mm² - in our example, this would correspond to the connection to the main fairway. Too thin a wire heats up, the voltage inevitably drops. Then, for example, not 12 V is supplied to the headlight, but only 10 or 9.5 V - the light becomes dim.

[This publication was borrowed from the website: fordbook]