Intro to electrical circuits and trade terms
Battery
A DC voltage source consisting of two or more cells that convert chemical energy into electrical energy.
Series Circuit
A circuit with only one path for a current flow.
Circuit
A complete path for current flow.
Transformer
A device consisting of one or more coils of wire wrapped around a common core. It is commonly used to step voltage up or down.
Insulator
A material through which it is difficult to conduct an electrical current.
Conductor
A material through which it is relatively easy to maintain an electric current.
Electron
A negatively charged particle that orbits the nucleus of an atom.
Mega
A prefix used to indicate one million. For example one mega-watt is equal to one million watts.
Kilo
A prefix used to indicate one thousand ; For example, one kilowatt is equal to one thousand watts.
Ohms law
A statement of the relationships among current, voltage, and resistance in an electrical current : Current [I] = voltage [E] divided by resistance [R]. Generally expressed as a mathematical formula : I=E/R.
Schematic
A type of drawing in which symbols are used to represent the components in a system.
Ampere
A unit of electrical current. For example, one volt across one ohm of resistance causes a current flow of one ampere.
Joule [J]
A unit of measurement that represents one newton-meter [Nm], which is a unit of measure for doing work.
Coulomb
An electric charge equal to 6.25 x 10^18 electrons or 6,250,000,000,000,000,000 electrons. A coulomb is the common unit of quantity used for specifying the size of a given charge.
Resistance
An electrical property that opposes the flow of current through a current. Resistance (R) is measured in ohms.
Relay
An electricalmechanical device consisting of a coil and one or more sets of contacts. Used as a switching device.
Solenoid
An electromagnetic coil used to control a mechanical device such as a valve.
Ammeter
An instrument for measuring electrical current
Voltmeter
An instrument for measuring voltage. The resistance of the volt meter is fixed when the volt meter is connected to a circuit the current passing through the meter will be directly proportional to the voltage at the connection points.
Resistor
Any device in a circuit that resists the flow of electrons.
Matter
Any substance that has mass or any occupied space.
Neutrons
Electrically neutral particles (neither positive nor negative) that have the same mass as a proton and are found in the nucleus of an atom.
Watt (W)
The basic unit of measurement for electrical power.
Ohm
The basic unit of measurement for resistance.
Nucleus
The center of the atom. It contains the protons and neutrons of an atom.
Voltage drop
The change in voltage across a component that is caused by the current flowing through it and the amount of resistance opposing it.
Voltage
The driving force that makes current flow in a circuit. Voltage (E) is also referred to as electromotive force or difference in potential.
Current
The movement, or flow, of electrons in a circuit. Current [I] is measured in amperes.
Valence Shell
The outer most ring of the electrons that orbit about the nucleus of an atom.
Power
The rate of doing work or the rate at which energy is used or dissipated. Electrical power is the rate of doing electrical work. Electrical power is measured in watts.
Atom
The smallest particle to which an element made be divided and still retain the properties of the element.
Protons
The smallest positively charged particles of an atom. Protons are contained in the nucleus of an atom.
Volt (V)
The unit of measurement for voltage (Electromotive force or difference of potential). On revolt is equivalent to the force required to produce the current of one ampere through a resistance of one ohm.
Ohmmeter
an instrument used for measuring resistance.
