Install event lighting and sound systems
What the exam tests
This core domain tests site survey, power distribution, load calculation, rigging safety, DMX control, audio signal flow, cable management, grounding, and weather protection for temporary event systems.
Core rules
- Survey the site: power source, floor loading, rigging points, cable routes, weather exposure, and exit paths.
- Calculate load before connecting: total watts divided by voltage gives current, then compare with breaker and conductor rating.
- Use certified rigging hardware and rated truss; never exceed the working load limit.
- Ground the system and avoid ground loops; use residual current protection where required.
- DMX512 uses a daisy chain, maximum 32 devices per line, and a 120-ohm terminator at the end.
- Keep audio and dimmer cables separated where possible; cross at right angles when necessary.
- Dress and ramp cables; keep walkways and exits clear.
Worked example
You have 12 LED fixtures, each using 4 DMX channels. Total channels = 48, which fits one universe. Addresses start at 1 and increase by 4: 1, 5, 9, ... 45. Reasoning: each fixture occupies a block of four channels; the last fixture ends at channel 48, so no second universe is needed.
Traps that cost marks
- Adding loads until the breaker trips instead of calculating first.
- Forgetting the DMX terminator or exceeding 32 devices on one line.
- Using unrated slings or guessing truss capacity.
- Running audio signal cable parallel to dimmer feeds.
- Leaving cables across walkways without ramps.
Key points
- Calculate current before connecting any load.
- Use rated rigging hardware and respect load limits.
- Terminate DMX and keep each line within 32 devices.
- Keep audio and power cables separated.
- Ramp and dress cables to protect walkways.