How do they make Christmas lights?
Automation to the rescue
So, how does the factory make a string of Christmas Lights? It really helps to have a specialized machine and a lot of automation. This YouTube video is a bit dated and mixes incandescent with LED lights but it does a good job of showing how automation works. It also shows the difference between lights wired in series and parallel. You’ll better understand the phrase “when one goes out they all go out.”