Christmas Light Plugs & Replacement Sockets

Confused by Spt-1 and Spt-2?

         Spt-1 and Spt-2 in a nutshell is the insulation rating of the wire, the wire gauge itself does not change (being the center core of copper). The advantage of having different insulation ratings is that a thicker piece of insulation will let you run more lights continuously. Spt-1 18 gauge wire can handle 7 amps (770 watts) and Spt-2 18 gauge wire can handle 10 amps (1100 watts). Adding another 3 amps to a run of lights can net you many more lights, for example if you were using standard C7 incandescent bulbs you could run 154 bulbs on Spt1 wire, whereas on Spt2 you could run 220 bulbs so 66 more bulbs on a single run!

Other advantages are that thicker insulation is tougher and could net you a few more years of use, UV is hard on insulation and cause it to crack and deteriorate, but using a thicker insulated wire helps give you as much use out of a wire as possible. Now you may think, "why doesn't everyone just use SPT-2?" well for products like LED bulbs or sets that use little power you may not need the extra amperage, and there is a higher up front cost.

Just remember to always match wire, plugs, and sockets to ensure that all your products will fit and work together properly.