1. Electricity and the devices that carry it.

2. POWER  Electricity and the devices that carry it.  Rules of Lighting Design  Law of Reflection  Law of Refraction  Inverse Square Law  POWER FORMULA

3. Electricity  Electricity  Watts -- Measurement of power required to do work  We often measure the amount of Electricity we use in watts.  Amps (Amperes) –Measurement of the flow of electrons (capacity)  Volts –Measurement of electrical potential (push)

4. Electricity  Power Formula Is:  P= IE  But my favorite is:  W=VA  Watts = Volts(Amps)

5. Electricity  Amperage is the measurement of electrical flow and is dictated by the capacity of the electrical devices we use.  Everything has a capacity.  Dimmers, Lights, Lamps, And...  CABLE!!!

6. Electricity  Cable Gage is Very Important.  We use 12 Gage Cable in the Theatre.  It’s actually 12/3 cable.  (that’s 12 gage, 3 wire)  12 Gage has a capacity of 20A  Other gages have other capacities (there’s a chart on page 81 of your book).

7. Stage Pin Connectors  Hot =or Red  Neutral =White  Ground =Green  http://www.d.umn.edu /~mharvey/th1501con nectors.html

8. Electricity  So using this formula, let’s calculate some situations.  How Many Cables?  How many 12/3 Cables do you need to connect the following lamps?  3 – 1000w (or 1K)  5 – 750w  2 – 500w  3 – 250w  Please show your work!

9. How Many Cables?  How many 12/3 Cables do you need to connect the following lamps?  2– 1000w (or 1K)  3 – 750w  5– 500w  3 – 250w  6 – 100w  Please show your work!