A lighting controller is a box that houses a number of dimmer switches. Each dimmer controls the amount of power going to a lighting instrument, so the light can be adjusted up or down in intensity. A controller box will always have three characteristics: a means to connect individual lighting instruments to the controller through "patch" outlets; a means to dim or turn off the power to each patch outlet; and a means to quickly connect the controller box to an available power source, such as 110 volt wall outlet(s) located in the performance space.
Lighting controllers are usually in the shape of a box with a base, four sides, and a sloping top. A controller box can be constructed of ¾ plywood. Openings for the switches dimmers, and patch boxes can be easily cut into the plywood with a saber saw. A hinged cover can be created to protect the top of the controller during transport.
Electrical wiring, outlets, switches, and dimmers each have specific "load" limits for the amount of electricity each device can handle safely. If these load limits are exceeded, the master circuit breaker for the performance space will trip, shutting off the power. Do the math carefully to distribute the power loads, asking yourself how many lighting instruments running what wattage of bulb or lamp do you want to use in your show? On how many dimmer switches rated for how many watts? All of which are powered by what kind of on/off switch rated to handle how many watts? Plan also for main power supply cord(s) coming into the controller box rated to handle so many watts of power. Start from the lighting instrument side of the schematic and work up towards the final component, the power cord, and mathematically plan how to safely distribute power through the entire system, without overloading any device. Design the dimensions of your controller box to accommodate this number of splice boxes, dimmers, patch outlets and on/off switches.
Electrical wires come in different sizes or gauges: No.12-gauge, 2-part wire with a ground wire is recommended. Purchase wire labeled "12/2/G--" with the addition of "M" for metal or "NM" for non-metal sheathing. All patch outlets and plugs should be the 3-prong grounded type. Use metal splicing boxes, with covers, to distribute power to switches or dimmers box inside the controller. Use plastic or metal boxes for mounting the switches and dimmers to the top of the controller. Switches that have power indicator lights are recommended. Dimmers come in several types, from round knob controls, to rocker switches, to sliders.