Electricity – A Primer
We could not have lighting if it were not for electricity. Electrification is the generation, distribution and use of electricity for homes and businesses. A basic understanding of electricity is useful in planning for lighting and in choosing fixtures. Electrical design and especially installation should be the responsibility qualified electrical professionals.
Electricity comes from the Greek word for amber which was known for its static electricity. Electricity is the movement of electrons along a conducting pathway. Electrons are negatively charged atomic particles. Matter has resistance to electron flow. Matter with the least resistance is called conductive, copper, silver, gold and water for example. Matter with the most resistance are insulators, paper, ceramic and wood to name three. Electricity flows when electromagnetic force is applied to a conducting pathway. The force is called voltage, the flow is called current.
Volts measure the electrical pressure that creates current. Electric utilities distribute electricity at very high voltage because they are sending power over long distances. Transformers, like the ones you see on light poles, reduce that voltage to 110-120 volts which is what most households use to run appliances and lights. Voltage can vary up or down by 5% without causing any problems but greater variances can damage appliances.
Current is the rate that at which electrons flow through a conductor. It is measured in Amperes, commonly called amps. Current is the function of electrical pressure and the amount of resistance in the circuit. Typical homes have a service that provides 150-200 amps. Large homes might have 400 amp services. A circuit is a closed path of electricity and includes the breaker or fuse, the wiring and the load. The load is the amount of watts used. A 20-amp circuit at 120 volts will support a load of 2400 watts. Watts measure electrical power and is a function of voltage and amperage (W=VxA).
Wow, that’s enough of that. But at least now you know have an understanding of why electrical professionals are necessary to install and design lighting systems. Please visit FoggLighting.com and let us know if you have questions, needs or questions. Be sure to download the free app from Underwriters Laboratories called LightSmart. Lots of good information.
A Sunday Factoid
Lighting accounts for only 5% to 7% of the total electricity usage in the average American home.