Is a light bulb an example of a load?
In a household setting, the most obvious examples of electrical loads include light bulbs and appliances. In a more general sense, any resistor or electric motor in a circuit that converts electrical energy into light, heat, or useful motion constitutes a load on the circuit.
How does a light bulb work easy?
The incandescent light bulb turns electricity into light by sending the electric current through a thin wire called a filament. Electrical filaments are made up mostly of tungsten metal. The resistance of the filament heats the bulb. Eventually the filament gets so hot that it glows, producing light.
What happens if you use a stronger light bulb?
Using a light bulb with too high of wattage can lead to overheating of the light bulb. This heat can melt the light socket as well as the insulation of the wires. Once that happens, you put yourself at risk of arc faults, and this is something that could even lead to property fires.
What type of load is a lightbulb?
A lightbulb (a plain old incandescent lamp) is typically brought up as an example of resistive load. Yet the filament is actually made of several feet of very thin wire cleverly coiled to form a filament which is about one inch long.
Can a 100W light bulb be used as a ballast?
They make good ballast resistors and dummy loads for a variety of devices. A 100W bulb starts at about 10Ω when cold and works its way up to about 150Ω, so they even adapt well to a wide range of voltages. Plus, they are cheap, available in a several values, and generally do not explode on failure.
How much current does a 20W light bulb draw?
The higher the light bulb power rating, the higher the current you will be able to draw in your load. For example, a single 20W 12V bulb would nominally draw about 20/12 = 1.67A at 12V.
How does an adjustable load on a lamp work?
As the duty cycle increases, so does the average current through the lamps, so you get — in effect — an “adjustable load.” However, this wouldn’t be a very useful circuit if we didn’t filter the abrupt changes in current from the load as the MOSFET turns ON and OFF.
How does a PWM work on an incandescent lamp?
An eight-pin PIC12F683 microcontroller (U2) is used to provide the PWM signal to the gate of the MOSFET. The internal ADC (Analog-to-Digital Converter) reads a voltage from a multi-turns potentiometer (POT) and adjusts the PWM duty cycle proportionally.