Ohm’s Laws for Direct and Alternating Current
In order to turn air into compressed air, you need power. This power comes in the form of electricity: Alternating Current or Direct Current. In this article we will give a short introduction to the laws of Ohm. These laws introduce resistance in the relationship between current and voltage.
What is Ohm’s law for direct current?
La ley de Ohm establece que la corriente a través de un conductor entre dos puntos es directamente proporcional al voltaje entre los dos puntos. Al introducir la constante de la proporcionalidad, la resistencia, se llega a la ecuación matemática que describe esta relación: U = R x I En la que I es la corriente a través del conductor en unidades de amperios, V es el voltaje medido a través del conductor en unidades de voltios y R es la resistencia del conductor en unidades de ohmios. Más concretamente, la ley de Ohm establece que la R en esta relación es constante, independiente de la corriente.
What is Ohm’s law for alternating current (and what is self-induction)?
An alternating current that passes through a coil gives rise to a magnetic flow. This flow changes magnitude and direction in the same way that an electric current does. When the flow changes, an emf (electromotive force) is generated in the coil, according to the laws of induction.
This emf is counter-directed to the connected pole voltage. This phenomenon is called self-induction. Self-induction in an alternating current unit gives rise in part to phase displacement between the current and the voltage, and in part to an inductive voltage drop. The unit's resistance to the alternating current becomes apparently greater than that calculated or measured with direct current.
Phase displacement between the current and voltage is represented by the angle φ. Inductive resistance (called reactance) is represented by X. Resistance is represented by R. Apparent resistance in a unit or conductor is represented by Z.
Related articles
30 junio, 2022
Garantice un funcionamiento seguro y fiable de la instalación eléctrica en instalaciones de compresores. Conozca cuáles son los factores esenciales relativos a la instalación eléctrica que debe tener en cuenta, desde los motores hasta la protección de los circuitos.
1 febrero, 2022
Learn about the basics of electricity and the role it plays in the compression of air. Some basic terminology and definitions.
16 marzo, 2023
To generate compressed air, an air compressor electric motor uses energy to produce power. This guide explains how they work.