What are the differences between SPT-1, SPT-2, and SPT-3 wire?

With the holidays coming and Christmas lights going up, SPT Wire is a hot topic. Its use in lighting makes SPT wire especially popular this time of year, but knowledge of SPT-1 wireSPT-2 wire, and SPT-3 wire is useful for much more than Christmas decorations. SPT wire is used in a multitude of applications, including lamps, small household appliances, and other light duty applications. Knowing the differences between the three different types of SPT cable can help you determine which product is right for you.

The main difference between SPT-1, SPT-2, and SPT-3 is the thickness of the insulation that surrounds the copper wires, with each SPT wire having a thicker insulation than the previous. Generally, a cable with a thicker insulation will also have a higher maximum amp rating.

SPT cables feature stranded copper conductors and polyvinylchloride (PVC) insulation, and resist oil, water, acid, alkali, and ozone. All three types of cable are rated up to 300 volts and 60°C or 105°C.

SPT-1 Wire is the most popular SPT cord. SPT-1 has an insulation thickness of .030”. Because it has the thinnest insulation of the SPT wires, it also has the lowest amperage.

SPT-2 Wire features a thicker insulation than SPT-1 Wire at .045” thick. As a result, SPT-2 also has a higher maximum amp rating, and is able to handle more power.

Because of its thicker insulation, SPT-2 cord is often recommended for lower temperatures where the insulation may get brittle and crack. However, the thinner insulation on SPT-1 wire tends to be more pliable, so some professional installers believe that SPT-1 is actually better for cold weather.

SPT-3 Wire is the newest type of SPT cable, and it also has the heaviest construction. While SPT-3’s insulation ranges from 0.060” to 0.110” thick, its maximum amp rating does not greatly vary from SPT-2 wire’s amperage.

When choosing between SPT-1, SPT-2, and SPT-3 cord, be sure to consider insulation thickness and amp ratings. Ultimately, your choice of SPT wire will depend on your application.