When it comes down to it, the main advantage of 240-volt power over 120-volt power boils down to one simple point, and it is referred to as Joule's Law, which is : Power is equal to voltage times current. Twice the voltage will transfer twice the power. Here are a few of the main differences between 240V power and 120V power.
Twice the Voltage, Twice the Power
All 240V power is part of what is called three-phase power. In a three-phase system, the wire is thicker, which equals less draw on the box. In addition to producing power, wires also create resistance. The thicker the wire, the more resistance, thus less draw. The benefit of creating less resistance is that it allows less of a chance for a breaker to slip when other devices turn on. This helps stop things from flickering when you turn on two items from the same breaker. This essentially means that an object running on 240V would take twice the power of a 120V before tripping the breaker.
When it comes to the lighting, the advantages of 240V power really shows. Commercial greenhouse lighting, outdoor floodlights, and stadium lighting may benefit the most from 240V power compared to 120V power, because these lights run off of ballast assistance, which is an electronic device used for starting and regulating fluorescent lights and discharge lamps. Also multiple ballast can be used at the same time. In a row of 10 lights, you are looking at anywhere from 4,000 to 10,000 watts of electricity, or 18 to 45 amps. For example, if you were to use 120V power and were trying to run 10,000 watts of light, you would need almost 90 amps from your breaker box, where as if you use 240V, that would be cut in half, allowing all of those breakers to be available.
As far as a monetary difference goes, there really is none. It may seem that since you are drawing less amps with a 120V that you are using less power, but you are using the same amount just through a different conversion. When more amps are open using 240V, there is a chance that the electricity bills will be higher, but only because using the higher of the two amps allows you put more things through them. For example, in an outlet that uses a toaster or a blow dryer, you would have to run one or the other with a 120V, but with a 240V, both can be used at the same time, and time equals money.
Things to Consider
Before purchasing 240V or arranging for installation of these lamps, there are some important things to consider. For instance, it is important to make sure that the main source of power will support all of the voltage. Most residential houses are not wired for 240V, and this requires getting a special permit from the city in most areas. It will also be necessary to hire a licensed electrician, which can be costly. This is one of the biggest deciding factors when choosing to purchase one over the other.
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