Fundamentals of Electricity Or…how to wire a plug without electrocuting yourself or half a dozen of your co-workers!

Electromotive Force (EMF)  Measured in: Voltage (E)  Amperage (I…for inductance)  And Resistance (R)

Electromotive Force (EMF)  Voltage or Electromotive Force Measurement of potential at any point in a circuit Another way to understand it is as pressure. Measured in Volts

Electromotive Force (EMF)  Amperage or Inductance Measurement of the flow of current through a circuit at any given point. Sort of like volume or flow of water through a pipe. Measured in Amps  Inductance is the generation of an electromagnetic field by the flow of electricity through a wire or coil of wire.

Electromotive Force (EMF)  Resistance Resistance to the flow of electricity at any given point in a circuit. Measured in ohms.  Ohm’s Law: As Voltage increases, Current increases; As Resistance increases, Current decreases.

Electromotive Force (EMF)  The formula: E=IR where E=voltage, I=current, and R=resistance.  Other configurations include I=E/R, and R=E/I  An easy way to remember is “Eagle, Indian, and Rock.”

The Power Formula, W=VA  Used to calculate (based on two knowns) Wattage consumption Current Or Voltage  Easiest way to remember as the “West Virginia Law.”  Other configurations include: A=W/V, and V=W/A

Wire Gauge  Standard sizes specified by the National Electrical Code (NEC)  Larger the number the smaller the diameter of the wire.  Gauge Amps

Electrical Circuit Types  Series Circuit: Voltage is shared equally with each load in the circuit.  Parallel Circuit: Amperage is shared equally with each load in the circuit.  A “LOAD” is any element within a circuit that resists – but does not halt- the flow of current (lamp, motor, or resistor, etc.)

Electrical Current  Direct Current Electron flow is in one direction and at a constant rate  Alternating Current Electron flow changes direction (polarity) in regular, repeated cycles.