# Electricity Basics

Electricity is the flow of electrons from one place to another.

Resistance measures how easily it flows. Ohms is the unit of measurement for resistance in a circuit.

Voltage is push or force of the electricity.

Amperage is the frequency, or rate of flow over time.

Matter can be broken down into:

- Conductors: electrons flow easily; there is low resistance.

- Semi-conductors: electron can be made to flow under certain circumstances. Resistance varies or is controlled.

- Insulator: electrons do not flow easily; there is very high resistance.

Ohm's Law: R = E / I

R = Resistance (ohms)

E = Electro-motive Force (volts)

I = Intensity of Current (amps)

Ohms = Volts/Amps

Wattage is the current, or total power.

Voltage (V) x Amps (A) = Watts (W)

West Virginia Rule -      W=VA

Most Dimmers in theater (all in BCPA):

120V x 20A = 2400W

Pay attention to the wattage of the fixture and lamp you are using before you decide

how many lights to tie together on the same circuit.

LAMP WATTAGE (On  a 2400 Watt Circuit)                                Number Of Lights Per Circuit

550                                                                                                                         4

750                                                                                                                         3

1200                                                                                                                       2

1500                                                                                                                       1

## Series Circuits

A Circuit is a controlled route for electricity to flow, from a source, through a output, back to the source.

Circuits can be series or parallel, or a combination of the two.
In a series circuit, each output has to complete the circuit. If one fails, the entire circuit goes down. The common example is christmas tree lights. ## Parallel Circuits

In a parallel circuit, each output is independent and one failure does not break the circuit. ## 3 Phase Power Distribution ## When untying power at the end of the day, reverse the order. Remember, if anything is plugged in, GROUND should be plugged in. 