Stage Electrical Tutorial Brian Lincoln 12/5/18 Strand 300 Series Console with Fader Panels and Processor Rev 9

Purpose of Electrical Tutorial To explain the basic functions of electrical power needed on a typical stage and describe the terminology What you will learn… Fundamental definitions of electricity and circuit Terminology used in electrical systems Differences between AC and DC Power forms Understanding of Voltage, Current, & Power How a Dimmer Circuit works Intro to Industry Plug Standards How to Calculate loads (power) in circuits 4/2/2019

Why is Electricity Important to Theater? Electricity provides the energy to operate all aspects of a modern stage Electrical power is consumed by …. Lighting Equipment / Light Board / Fixtures Audio Gear / Amplifiers / Mics / Mixers Motor Drives / Winches Communications / WIFI Computers / Printers Stage Props / Foggers / Lamp post / Animatronics Utility: Chargers / Microwave / Hair Dryers / Fridge 4/2/2019

Electrical Energy Provided in 2 Forms Alternating Current (AC) Wall Outlet Dimmer Outlet Transformer Generator Direct Current (DC) Battery Power Supply (Converts AC to DC via transformer) 4/2/2019

Electricity Performs Work Electrical Energy is delivered to a load via a circuit Load is any entity that consumes power to perform useful work, e.g., light bulb, motor, amplifier, drill, table saw, computer The Electro Motive Force (EMF) or potential source (Voltage) provides electromagnetic pressure to push electrons down a wire (Current) The combination of voltage and current create “Power” or energy per time 4/2/2019

Electrical Circuit – DC Analysis Switch + Potential Source (EMF) Load - 4/2/2019

Electrical Circuit – Closed Loop Switch Current (Amps) + + Potential Source Voltage Work Load - - Moves Something Generates Light Generates Heat Amplifies Sound Performs Calc Transmits RF Operates Cell Phone 4/2/2019

Electrical Circuit – Ohms Law Switch I - Current (Amps) + + Potential Source V – Voltage (Volts) Load R – Resistance (Ohms) V Meter - - Ohms Law Where: V = Voltage (Volts) I = Current (Amps) R = Resistance (Ohms) V = I x R 4/2/2019

Electrical Circuit - Power Switch Work (Power) I - Current (Amps) + + Potential Source V – Voltage (Volts) Load R – Resistance (Ohms) - - Ohms Law Where: V = Voltage (Volts) I = Current (Amps) R = Resistance (Ohms) Power Law Where: P = Power (Watts) I = Current (Amps) V = Voltage (Volts) V = I x R P = V x I 4/2/2019

Electrical Circuit – Parallel Loads Switch ITotal I2 I1 + P1 P2 + + + Potential Source V – Voltage (Volts) Load 1 Load 2 - - - - R1– Resistance (Ohms) R2 – Resistance (Ohms) ITotal = I1 + I2 PTotal = P1 + P2 Loads Can Be Calculated using Current or Power 4/2/2019

Electrical Circuit – AC vs DC Direct Current Circuit (DC) Alternating Current Circuit (AC) 1st Half Cycle Switch Current (Amps) Current (Amps) + Switch + FLOW AC Voltage Potential Source Work Load Current (Amps) + - - + Potential Source FLOW DC Voltage Work Load - - One Direction 2nd Half Cycle Switch Current (Amps) Current (Amps) + + FLOW AC Voltage Potential Source Work Load - - Reverse Direction 4/2/2019

AC vs DC Waveforms DC Power AC Power Volts Volts AMAX = Peak Voltage ARMS = AMAX x 0.707 AAVG = AMAX x 0.636 12V +12V Root Mean Square (ARMS) Average (AAVG) Peak AMAX Time Time Zero Crossing -12V Period (T) One Cycle Frequency = 1 / T 4/2/2019 Example: 60 Hz => 16.67ms Period

Standard North American AC Power Edison Power 120VAC @60Hz (RMS) Typical Wall Outlet (3 pin) Always on… not dimmed 20 Amp Circuit Breaker 120V x 20Amp = 2400 Watts Volts +170V Root Mean Square (RMS) +120V Peak Time -170V Period (T) 16.667ms 60 Hz 4/2/2019

Where Does Edison Power Come From? Neutral Hot Ground 4/2/2019 Service Panel Outlet

Circuit Breaker Protects Over Current Draw Circuit Breaker is designed to open the circuit loop if the current draw exceeds the rating of the breaker Provides Protection…Watchdog Without a Breaker, drawing too much current can over heat the wires and cause a fire Circuit Breaker is triggered internally via thermal mechanism; High current results in temperature increase, tripping the breaker If over current draw trips breaker, it can be reset by flipping switch off, then on again 4/2/2019

Dimmer Circuit Power Forms Strand Dimmer Outlet 120VAC @ 20Amps (2400 Watts) with 0 to 100% dimming capability typically for light fixtures Found on the Electric Bars and various ground level stations around the stage walls Use 3 pin Twist Connector (typically) but can also accommodate an Edison Nema 5-20 or 5-15; 3 pin plug Do not run motors (inductive loads) on the dimming circuits; Only run Resistive loads such as incandescent bulbs Dimmer packs located in the attic in Stack 4/2/2019

Basic Lighting System Block Diagram Light Board Controller In Tech Booth DMX Bus Dimmer Stack In Attic Dimmer Dimmer Dimmer Dimmer Dimmer Dimmer Back Stage or on Electricals Near Lights Dimmer 1 Outlet Dimmer 2 Outlet Dimmer 3 Outlet Dimmer 180 Outlet 120 VAC 120 VAC 120 VAC On Gaffers, Battens and Electricals (above stage) Light 1 Light 2 Light 3 Light 4 Light 5 Light 6 Light 7 4/2/2019

How Does A Dimmer Work? Dimmer Stack (In Attic) DMX Bus (Address and Data) 120 VAC Power Source Micro Controller Triac Dimmer #123 Micro Controller Triac Dimmer #124 Micro Controller Triac Dimmer #125 Micro Controller Triac Dimmer #126 DimmerOutlet DimmerOutlet DimmerOutlet DimmerOutlet Light Bulb Light Bulb Light Bulb Light Bulb Dimmer Units receive signal from Light Console through DMX Bus Convert small signal to high current output to light fixture 4/2/2019 18

Dimmer Circuit – Pulse Width Modulation (PWM) Volts Volts Volts Time Time Time 0% (Off) 25% 50% Area Under Curve is “On Time” Volts Volts Time Time 90% 100% (Full On) 4/2/2019

Strand Dimmer Rack – Stage 192 Dimmer System Dimmer Pack Inserted in Rack 2 Control Computers 4/2/2019 Dimmer / Control Rack 2.4 kW Dual Dimmer Pack

180 Dimmer Outlets – Located Around Stage Dimmer Address and relative location on Electrical Bar The 4 “Electrics” above Stage The 2 Catwalk “Electrics” In front of Stage At Ground level On Wall In Ceiling On Batten 4/2/2019 Dimmer Outlet Boxes Dimmer Outlet Boxes (Above)

Typical DC Power Forms On Stage 12 VDC Wall Wart @ 3 Amps (Transformer) 24 VDC Wall Wart @ 5 Amps (Transformer) USB 5V @ 2 Amps (Transformer or Regulator) Batteries AAA 1.5VDC @ 3 Amps AA 1.5VDC @ 3 Amps 9VDC @ 500mA 12VDC Lead Acid @ 300 Amps 4/2/2019

Power Plugs NEMA 5-20 or 5-15 for Edison Power NEMA L5-20 Twist for Dimmer Power Stage Pin Plugs (Not used at IRHS) PowerCON for Edison Power COAX 2.1mm for 12VDC and 5VDC Wall Warts COAX 2.5mm for higher current draws USB for 5VDC 4/2/2019

NEMA Plug /Outlet Edison Power Circuit For Stage Edison Power Circuit For Home and Stage Dimmer Power Circuit 4/2/2019

Typical Plugs Used on Stage NEMA 5-15 NEMA 5-20 NEMA L5-20 Edison Stage Pin IEC PowerCON 4/2/2019 Stage Pin

Typical DC Plugs & Transformers 2.1mm & 2.5mm Coax 6VDC Wall Wart 2.1mm Coax 12VDC Power Suppluy 2.5mm Coax 4/2/2019 USB 5VDC

Calculating Loads Add up number of loads on a circuit using current or power rating and assess if greater than circuit breaker rating Try not to load circuits to full capacity… leave margin of 25% to 50% Example 1: Qty 3 of the 575W Ellipsoids on a 2400W dimmer outlet circuit… 3 x 575W = 1725W which is less than 2400W (72% loaded) …OK! Example 2: Qty 2 foggers (12 Amps each) on a 20 Amp Edison outlet circuit… 2 X 12 Amps = 24 Amps which is greater than 20 Amp (120% loaded)…NOT OK!! 4/2/2019

Stage Light Fixture Examples PAR Cyc Ellipsoidal 300W 500W 575W to 1000W Slide Projectors Scoop Flood 200W Fresnel 200W 500W 4/2/2019

Motion Lights Fixtures MAC 250 13 Channels Q Spot 200 10 to 14 Channels 325W 334W RUSH 16 Channels Intimidator (Scanner) 5 Channels 4/2/2019 300W 165W

LED Intelligent Fixtures 100W 40W 50W 4/2/2019 50W 30W

Lumens and Watts Conversion Charts Lumens for Light Source Watts Lumens Incandescent Watts LED Watts 375 25 6 450 40 10 800 60 15 1100 75 19 1600 100 2600 150 38 3000 200 50 14,000 575 233 21,900 750 365 Luminous Efficacy Light Source Luminous Efficacy (Lumens/Watt) Incandescent 12-18 Halogen 16-24 LED 30-90 Efficiency of Light Source (How well it converts electrical power into light power) Higher ratio is better Light Output (Luminous Power) Electrical Power Consumed 4/2/2019

Summary Electricity provides energy to perform work on a stage Comes in Alternating Current (AC) or Direct Current (DC) forms An electrical circuit must be closed to deliver power to load 120VAC power - Edison is always on whereas a Dimmer circuit is adjustable from 0 to 100% Ohms Law and Power Law govern electrical behavior Power plugs are sized and rated per their current capability; Come in various sizes and shapes Circuit Breakers provide overload protection Parallel Loads can be assessed by adding up current or power and compared to circuit breaker rating LED Lights provide more Lumens than Incandescents with less power consumption Understanding the concepts of electricity make you a smarter and safer stage tech 4/2/2019