Types of Electrical Wiring
The 3 types of electrical circuits your home may be using
Electricity is a great thing, don’t ya think? It powers everything we use on daily basis to keep us happy. I mean think about it, if you didn’t have electricity to power something like your A/C, you’d be pretty upset. But how much do you really know about electricity or how it is wired throughout your home? It’s time to learn the basics!
You may have heard the phrase “completing the circuit” before. But what does that really mean? Completing a circuit is basically what happens when a circuit is closed. This seems conflicting to our brains though… Usually when we think of a source of electricity being “closed,” we start to automatically think that this must be a circuit that is receiving no power. Well contrary to popular belief, it means the exact opposite. A closed circuit or complete circuit, is one that is free from breaks or anything that will hinder a current’s flow.
This whole “closed circuit” thing is just one of the many confusing aspects to how electricity works. This post is here to help you gain at least a little bit of understand about the wiring and electrical world.
- open circuit – is one where the continuity has been broken by an interruption in the path for electrons to flow, electrons cannot flow through it.
- closed circuit – is one that is complete, with good continuity throughout. They provide a direct, low resistance, path for electrons to flow through.
- resistance – is the measure of opposition to electric current.
- switch – a device designed to open or close a circuit under controlled conditions.
- short circuit – is an electric circuit offering little or no resistance to the flow of electrons. Short circuits are dangerous with high voltage power sources because the high currents encountered can cause large amounts of heat energy to be released. Short circuiting is the number one cause of house fires and home electrocution incidents.
- current – a flow of electric charge carried by moving electrons in a wire.
- voltage – the difference in electrical potential between two points in a circuit or the electrical pressure that causes the electrons to move in a conductor.
- hot wires – provide the current source. (the top half of the circle in the diagram below)
- neutral wires – provide the return path for the current provided by the hot wire. (the bottom half of the circle in the diagram below)
A Simple Closed Circuit
A prime example of series wiring is Christmas tree lighting — if one bulb dies, so do the rest. This is why this kind of wiring is rarely used today. Series wiring routes the hot wire through several devices and then joins the neutral wire, which leads back to the source. There is only one path in a series circuit in which the current can flow.
A very mathematical way to put it would be to say that in a series circuit, the current through each of the components is the same, and the voltage across the circuit is the sum of the voltages across each component. For example, if there were a series circuit with 4 light bulbs and one 6 volt battery connected to it with a wire that ran from one bulb, to the next bulb, to the next bulb, to the next bulb, then back to the battery, there is same current running through all of them, and the voltage is 1.5 volts across each bulb. In a series circuit the currents stays the same, but the voltage decreases.
Switch wiring is a very basic concept. Switches are installed on hot wires and allow or disallow the flow of current to a light or other device. The act of flipping a lightswitch is a perfect example of this. In the OFF position, the current is being disrupted from traveling all the way through the hot wire and to the light bulb. In the ON position there is no blockage of current to the light bulb.
The most common form of home wiring is parallel wiring, where several different devices are powered on a single circuit. In parallel wiring both the hot and neutral wires run through the various housing boxes along the route and branch off to individual fixtures and appliances. The hot and neutral wires run from your electrical panel to the device that needs power.
So remember that 6 volt battery and 4 light bulbs we were talking about earlier? Well in a parallel circuit, each light has its own circuit (or its on hot and neutral wire) and the voltage across each of the components is the same; the current increases, but the voltage stays the same. The currents through the light bulbs combine to form the current in the battery, while the voltage drop is across each bulb and they all glow. This allows that 6 volts of electricity to run to each of the light bulbs, all at the same time if you desire.