The electrical theory is a cornerstone in the study to becoming an electrician . Concerning the topics which discuss many important things such as what electricity is, how current is generated , as well as the jargons which, which not necessarily esoteric, are often used by electricians themselves.
Electrical Theory for Electricians
As much, there are people outside of the field who would find the terms voltage, resistance, current, electric potential, and electric charge something quite familiar—as probably learned in high school—yet, at the same time, only so at the basic understanding.
If you are that person, this is a refresher topic for you as it deals with everything you would need to know about the Electrical Theory:
A Result of Ages-long Discovery
Everything about electricity was once a science obscure to the world. This was most ostensive at a time when the world was still dependent on fire for lighting during dark.
The discovery of electricity did not necessarily happen over night and was not laid out by just one man—over time, there had been many, each of which subsequently adopting on existing knowledge and even finding new studies as well as innovating on such discoveries.
But it all harkens back a few millennia ago.
Unbeknown to us, we may already have first encountered electricity when the first man discovered fire by employing the power of heat-generating friction, as told by science.
Even after several centuries at around 600 B.C., the world at large is still ignorant in the existence of electricity—at least, at the time, a non-existent phenomenon. But the Greeks during this time had unwittingly discovered “static electricity” when they notice that rubbing fur on an amber creates a reaction between the two.
It took another several centuries later, specifically around the 17th century, before electricity and its components became conceptualized, thanks to the framework of science.
The Term “Electricus” Was Coined
From something borne out of mystery, the name “electricus” was birthed in order to give name to what will subsequently be called “electricity,” thanks to the genius minds of English physician William Gilbert and English scientist Thomas Browne, respectively.
Lightning Was Known to Be Synonymous to Tiny Electric Sparks
The discovery that the lightning is not any different from tiny electric sparks was credit to Benjamin Franklin who made an experiment using a kite and a key during a storm. This was back in 1752.
Electric Current was Discovered
Electric current—or the flow of electric charge across a certain point or region—was discovered in the 1800, thanks to the curious mind of Alessandro Volta who initially discovered that electricity can be produced as a chemical reaction.
Tapping on that knowledge, he developed the so-called “Voltaic Pile”—or the primitive version of today’s battery—which is known to produce a steady flow of charged energy. Volta also learned how to transmit such energy by linking connectors from their two opposite charges.
The First Electric Generator was Developed
31 years after Volta’s discovery of electricity and the electric current, Michael Faraday invented an unrefined power generator it calls an electric dynamo which paved its practical usage. Faraday’s early invention employs the power of magnet and copper which create small electric currents to pass through a wire.
Lightbulbs were subsequently developed, thanks to the ingeniousness of Faraday’s discovery, but it was not until 1878 when the first true practical bulb—the incandescent bulb—was made. Individually, Thomas Edison and Joseph Swan were credited for the creation of the incandescent bulb.
Electricity Was Used to Light Society
By 1882, Thomas Edison’s direct current system (DC) has been providing energy for the street lamps of New York.
Alternatively, offering an alternative viable solution is the brilliant Nikola Tesla who developed the alternating current system (AC) which, while not necessarily better than the DC system, is conditionally used to this day.
What is Electricity?
Simply put, an electricity is a form of energy that is produced from the presence of charged particles—protons or electrons. Electricity can be generated via two means—statically, as in when the charge accumulates, or dynamically, which results from a current.
The Basics of Electrical Theory
The basics of electrical theory consist of the fundamental concepts about everything which we know and employ involving electricity. In a nutshell, it is best dissected into the following: circuits, electromagnetism, and electrical generators, motors, and transformers.
• Circuits
The circuit is the practical groundwork of electricity. Basically, a circuit is a pathway through which electric current flows. There is one simple logic about circuits in general—if it is closed, electricity passes through without hitting a dead-end; but if it is open, then the flow of electricity stops.
Yet, a circuit is only a simplification of how energy flows in a given schematic. There are also essential elements at play in it, each of which supposedly working harmoniously with one another, which involves the voltage, current, and resistance.
o Voltage: Also known as “electromotive force” (EMF) in certain conditions, the voltage is the force that makes electric charges move.
o Current: Current is the measure for the rate of flow of electricity after reaching a certain point.
o Resistance: Resistance is yet another major player in any electric circuit whose purpose is to limit the amount of current for practical reasons or, in other applicable cases, to terminate the flow of current altogether.
• Ohm’s Law
Named after Georg Ohm for having laid out the groundwork for the measurement of voltage and current given a certain length of wire, but not made by himself, the Ohm’s Law is a simplified justification of the proportionality among the three critical elements of a circuit. The law also suggests that finding the value for one element is possible given the identification of the other two.
• Electromagnetism
Discovered in 1821 by Hans Christian Orsted, electromagnetism is described as the interaction between electric current or electric field as well as magnetic fields. The discovery came when Orsted noticed a reaction between an electrically-charged wire and a compass needle when exposed to one another.
• Electric Generator
Based on the concept of electromagnetic induction as discovered by Faraday, an electric generator is an application of the physics between electrically-charged conductors and magnetic fields which essentially converts mechanical energy to electrical energy.
• Electric Motor
The complete anti-thesis of electric generator, the electric motor is a reverse concept wherein electric energy is used to generate mechanical energy.
• Electric Transformer
Unlike the previous concept whose undertone involves the conversion of energy from one form to another, the electric transformer is more of a transmitter of energy from one circuit to another.