The products themselves are simple enough; wire, plugs and socket! But the problems can come into play in the assembly of them. The most common problem people run into is almost certainly an arc'ing in the line somewhere. A point in your assembly at which both the positive and negative wires are touching or otherwise connected to each other.
This is most commonly caused by not properly finishing out both ends of the strand - ie making sure you have a male plug on one end and a female plug on the other end. We often see folks simply cut off one end of the wire without either trimming it or putting a plug on it. This can easily create an opportunity for the exposed pos/neg wires to touch, creating an arc
The second most common cause is improper installation of the sockets themselves. We recommend the use of a pair of something like these C clamps: https://www.amazon.com/Hobart-770560-Locking-C-Clamp-Pliers/dp/B002VECKXI/ref=sr_1_17?s=hi&ie=UTF8&qid=1476760783&sr=1-17&keywords=welders+pliers
... use those for popping the sockets onto the wire and you will have the best shot of a clean install and it will be much easier on your hands than any other method. If you have a bad socket install along the strand somewhere, this will also create a potential failure point. You have to make sure that the pins on the socket bite into the correct sides of the wire. If you have one that is in the middle of the wire, it will create a failure point.
The third most likely culprit for create a potential failure point will be at the plugs themselves. Just like the sockets, make sure the plugs have a good bite and are not bent over and are not piecing through the middle of the wire.
Another tip: The wire has one side that is slightly ribbed and the other is smooth. Make sure that the ribbed side is connected to the wider plug on the male end and on the wider opening on the female end. hen make sure that you sockets follow the same polarity pattern all the way down the strand.
If you have done all of these things there should not be a failure point anywhere in your strand.
