For example you might see yellow wires as switch legs to ceiling fans structural lights and outlets paired with light switches. The color of the sheathing indicates recommended usages.

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Yellow wire in light switch. Twist like wires together if there are any. Trim it so the exposed wire is the same length as the wire stripped for the dimmer lead. Trim the insulation as needed so the new end is free of any insulation. A double check would be to remove the switch that controls the light and see if its yellow in there. Wires are often black for live white for neutral and plain copper for ground. Not sure ive seen redblue cable outside of control cables.
Blue yellow violet and brown wires often act as the travelers to transfer power between the switches in 3 way and 4 way switch applications. For example white sheathing means that the inner wires are 14 gauge and yellow sheathing indicates that they are 12 gauge. Yellow and blue wires these wires usually come in pairs and pulled in conduits. Bit concerned about the colouring though. Attach it to one of the dimmer leads with a wire nut. Look up in the wire housing on the ceiling or the wall and pull the wires out.
Blue and yellow electrical wires while wires in these colors carry power they are not used in typical outlet wiring. They are used as hot wires and control electrical items like lights switched outlets and fans. Blue wires are generally used in a three way and four way switch applications by travelers. The old method of a 2 wire drop is explained along with the current code requirements of using a 3 wire cable. Youll use yellow mainly as switch legs to fans structural lights and switched outlets. These colors are used for the live wire pulled through conduit.
This shows wiring a light switch when the power comes into the light outlet first. The sheathing binds the inner wires together and its outer markings indicate the number of wires and size of wire gauge within the sheathing. Connect the wires from the light fixture to the wires from the house. Cut the yellow wire back to where it was taped leaving an appropriate length of exposed wire. Yellow and blue electrical wires are also used to carry power but are not for wiring the outlets for common plug in electrical devices. Well it certainly looks like that is the correct way it would be wired.
Instead blue and yellow wires are used as the live wires pulled through a conduit.