ac light bulb vs dc light bulb

Is An AC Light Bulb Better Or A DC Light Bulb ? - Please Tell Me

What’s The Difference between AC and DC Lighting and Light Bulbs?

Lets start off by making it clear to everyone , both voltage are for different application and has its own usefulness , so they should not be compared as they serve different purposes.

The terms AC and DC ( Alternating current and Direct current ) , are terms that everyone has learnt in their high school science classes. But when it comes to light bulbs, what is the difference between AC and DC lighting and light bulbs? To get a better understanding at this, we can go ahead and  get a recap on what exactly is AC and DC.

The magnitude and direction of an alternating current changes while that of a direct current remains in the same direction. Alternating current is the form in which businesses and residences
receive their supply of electricity. In alternating type of current, the current in the circuit constantly goes back and forth. The alternating current is supplied by a power plant. All residences typically have alternating current delivered to them by a substation which is fed by the power plant. The direction of the alternating current switches back and forth 50-60 times per seconds. This is known as the hertz (hz). The hertz is the reason why a light bulb appears to be glowing constantly, in spite of the current switching back and forth so many times.

AC voltage also allows us to use a magical device called a transformer, the transformer allows us take in voltage and current on one line, then output a different voltage and current with the same total power ( watts ) on another line. We can not do this efficiently with DC power. So  AC power is utilized because it;s voltage can be stepped up to super-high levels, and drop the current to a trickle. Making it ideal for long distance transmission.

Using alternating current saves power because it uses a higher voltages to send smaller currents, which also significantly reduces heating in wires, which is known as resistance. Transformers can convert a current that is high voltage into a current that is low voltage and vice versa. Alternating current is even faster to travel when it is high voltage, which is why transformers increase the voltage when the current is sent and other transformers decrease the voltage before it is redirected to houses and businesses. Direct current can also be used in lighting and bulbs but a lot of power is expended as well a lot of effort to send it to distances that are far away. Let's put it this way, DC current in low voltage cannot travel very far without losing its power. Further away it has to travel, the thicker the wiring is required. Which can become very costly.

DC - Direct current, on the other hand, comes from battery sources, bridge rectifiers, solar panels, cars , boats , etc. The current is made to go through conductors as well as semiconductors and insulators. Wires are an example of conductors. Direct-current wiring is usually one red one black with red being positive and black being negative.

All electricity distribution the world over uses alternating current because of its many advantages with regards to transmissions and the use of transformers. If direct current is required, then the alternating current that is distributed to a substation is converted into a direct current.

In a light bulb, the filament in the bulb acts as a resistance to the electrons that otherwise flow without impediment through the wire. Although the electrons can still pass through the filament, just like they pass through the wire, this requires more effort on their part. It is this work that the electrons have to do to overcome the resistance caused by the filament that generates heat that makes the filament light up.

If an electrical device can convert AC to DC and vice versa, it does not matter what type of current is supplied to it. For light bulbs and heating elements, both AC and DC will work as long but the fact is that though all electric devices require direct current, alternating current is what is used to deliver electricity with the help of transformers which convert AC to DC for the use of electric devices.

So in a nutshell , AC household light bulbs are good for household use where almost all electricity is supplied by providers that utilize a AC current. DC light bulbs are good for remote and self standing power supplies , such as DC batteries , cars , boats , yachts , solar off grid systems , trains , airplanes and more. The distance between the power source and the light itself is not too far and power can still be distributed without a large loss. 

 

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6 comments

I HAVE A OVERHEAD CRANE WHICH OPERATES ON 240VDC CAN I USE A 120VAC PILOT LIGHT OR DO I NEED DIFFERENCE VOLTAGE PILOT LIGHT ?

DAVID DEVINE

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