TERMS & DEFINITIONS
Electricity – The movement of electrons from a location of a greater number (positive) of electrons to a location of lesser number (negative) of electrons.
Positive – A location of the greater number of electrons.
Negative – A location of the lesser number of electrons.
Ground – A connection or conductor that can be traced back to an earth connection.
Grounding – The process of connecting a device or system to an earth connection.
Circuit – The path that electricity can travel (from the positive to the negative).
Resistance – The amount or willingness a material (solid, liquid, or gas) allows electrons to pass through (from positive to negative).
Ohm – The practical unit used to measure resistance.
Conductor – A material that has low resistance and readily allows electrons to pass through.
Insulator -A material that has high resistance and does not readily allow electrons to pass through.
Voltage -The level of energy or excitement being carrier by an electron.
Volts – The common name for the measurement of an electron’s energy.
Amperage, Current or Load -The amount of electrons moving (through a conductor).
Amps -The common name for the amount of electrons moving (through a conductor).
Wattage -The amount of work or energy being used or required by a device or process.
Watts -The common name for the amount of energy being used or required by a device or process.
Kw or Kilowatts – Watts divided by 1,000. Example :10 Kw = 10,000 watts.
TYPES OF CIRCUITS
Series – A circuit where two or more devices (resistance) are connected in a line so electricity must pass through each device.
Parallel – A circuit where all devices (Resistance) are connected to a “hot” conductor so they can equally receive the same amount of electricity.
Mixed – A circuit that has both series and parallel parts. An example of a mixed circuit is when you use a dimmer to adjust one or more lights
ELECTRICITY TYPES
Static – A naturally occurring form of Electricity that only lasts for short durations.
DC or Direct Current – A type of both naturally and artificially produced electricity where electrons flow in one direction from the positive through a circuit to the negative end on the circuit.
AC or Alternating Current – An artificial form of electricity where electrons flow for a time in one direction (positive {+}) and then for an equal amount of time flow in the reverse (negative {-}) direction.
AC (Alternating Current) TERMS
Cycles (Hz) – The number of times per second the current in AC alternates between positive and negative (also expressed in Hertz).
60 Cycle (Hz) – The North American standard for AC ( Europe is generally 50 Cycle).
Volts, Amps & Watts – Are all used in AC
Kw or Kilowatts – Watts divided by 1,000. Example :10 Kw = 10,000 watts.
KVA – KiloVoltAmps – Used to quantify the output of three phase transformers or generators. To get the Kw output multiply the value by .8. Example a 45Kva Generator (3 phase) produces 36Kw (45Kva X .8 – 36Kw)
Supply Lead or “Hot” Conductor – A connection or conductor having any voltage (greater than zero).
Neutral – A zero voltage (0v) connection or conductor in an Alternating Current System that can be artificial or .grounded In 120,277 & 347VAC (CA) circuits it is used to complete a circuit. Also carriers the unbalanced load between single and three phase systems. Can be used to measure the voltage, with a “hot” connection or conductor.
Balanced load – When the amps being used in a system are equal among all conductors.
Unbalanced load – The difference between the amps being used on each conductor or connection is a system.
AC ELECTRICAL SYSTEMS
Phase – A “hot” connection in AC that cycles a set number of times per second (60 in US) from + to -.
Single phase– A term used only for AC systems where either one (1) or two (2) “hot” conductors are present along with a neutral. This type of power is common in residential and small commercial locations. Normally limited to no greater than 200 amps.
Three phase– A term used only for AC system where there are three (3) “hot” connections or connections. Each “hot” connection is 120 degrees “out of sync” with its adjacent “hot” connections.
“Y” or “Star” three phase – Identifies a type of three phase power that has either a artificial or ground neutral creating a four (4) wire system.
“Delta” or Triangular three phase – Identifies a type of three phase power that doesn’t require or provide a neutral and therefore only has three (3) wires in the system
Industrial Delta – A Delta system that also has a (artificial) neutral that is capable of providing a single phase AC System (2 hots and a neutral).
