A chart to determine the limited possible hookups for your type and size of box, given the number and type of cables that come into it. New window

Understand the chart and its limitations: How to use this Cable-and-Box Chart
  1. In the chart, find the number and type of cables in the box you are working on.
  2. Look across from there to the type of box it is. Pick the first line listed. Then...
  3. Look up that combination's code letters in the Cable-and-Wire Functions Chart above. If the meaning of your letters makes no sense for what you already know about the switches, outlet, or light you are dealing with, look up the next combination listed in your cell of this chart below, until you find one that seems likely.
  4. Now try hooking up according to the wire uses of those cables, with help from the references in that chart, from the diagrams above, and from section "4" below.
  5. If your hookup does not work much, try any alternate hook-up that would match those same uses, and then go on to consider and try out the next combination from this chart below. If your hookup almost worked perfectly, try minor changes one at a time.