Difference Between SPT 1 and SPT 2 Wire

Wire thickness, also known as a gauge, is one of the top considerations when looking for an electrical cable. You want a cable with a thickness that matches the electrical resistance and current rating of the connected appliances.

Wires with larger diameters (which ironically have smaller gauge ratings) have a better current carrying capacity than those with smaller diameters. Thicker wires also tend to be more resistant to mechanical damage than their thinner counterparts, thus affecting their durability.

Gauge differences also happen to be the biggest consideration when choosing between SPT 1 and SPT 2 wires. This article offers more insights into the core differences between these popular wire types.

What Is An SPT Wire?

Before we delve into the differences between SPT 1 and SPT 2 wires, it would be best to begin by understanding what an SPT wire is.

An SPT wire goes by numerous other names, including an SPT cable, a lamp cable, a lamp cord, and a lighting cable. It refers to a portable cable designed to be used with household appliances and light-duty applications.

Appliances that utilize SPT wires include radios, clocks, fans, and extension cords. These wires are commonly used for holiday lighting decorations, particularly Christmas decors. You might also find SPT wires in any low-power electrical equipment, such as air-cons and refrigerators.

What Does The Abbreviation SPT Stand For?

The abbreviation SPT stands for Stranded, Parallel, and Thermoplastic. It’s a designation found on numerous flat fires. The acronym usually precedes a number that denotes the wire’s insulation thickness.

But what does each term represent?

In electricity, stranded wires refer to thin, bundled wires that are compressed and insulated using a non-conductive material. Stranded wires stand out for their incredible flexibility, making them excellent for use in electronic components situated in cramped spaces. That flexibility makes these wires easier to twist and bend to fit specific geometric shapes.

Parallel circuits refer to electric circuits comprising branches that divide the current such that only part of it flows through each branch. Despite the variance in current across the branches in parallel circuits, all branches have the same voltage or potential difference.

Lastly, thermoplastic is an electric term mainly used for insulation. It refers to insulation made from compounds that detach upon the application of heat. This mechanism allows the insulation to respond to extreme temperature fluctuations without causing damage to the copper wires.

SPT wires are some of the most easily recognizable electrical cables. That’s mainly due to their usage on common household devices. However, confusions abound regarding the differences between SPT 1 wires and SPT 2 wires. So, how do these wires differ?

Differences Between SPT 1 Wires and SPT Wires

The fundamental difference between SPT-1 and SPT-2 wires lies in the thickness of the insulation material surrounding their respective copper wires.

SPT-1 wires have an insulation thickness of 0.03 inches, compared to 0.045 thickness for SPT-2 wires. If expressed in percentages, SPT-2 wires have 50% thicker insulation than SPT-1 wires.

The difference in insulation thickness between SPT-1 and SPT-2 wires determines the nature of appliances each wire can be used with.

Due to their flexibility, SPT-1 wires are better suited for higher temperature applications. They are also easier on the environment, releasing a lower carbon footprint. SPT-2 wires are less brittle and hence less susceptible to cracking. Therefore, these wires are ideal for use with lower temperature applications.

The difference in usage between SPT-1 and SPT-2 wires is also reflected in their overall price. SPT-2 wires tend to be more expensive than their SPT-1 counterparts.

But despite their difference in insulation gauge, it’s worth noting that SPT-1 and SPT-2 wires have the same maximum amperage. That’s because the power handling capabilities of a 3 wire electric cable depend mainly on the amount of copper in the cable and the length of the wire in use. It has nothing to do with the thickness of the insulation material. In this respect, it’s generally observed that thicker and shorter copper wires carry higher amperage compared to thinner and longer ones.

Another thing worth noting is that despite their lower insulation thickness, SPT-1 wires are still remarkably resilient in harsh weather. According to experts, if seasonally used, SPT-1 wires can hold up well in most weather conditions. These wires can serve you well in various climates, including warm, tropical, cold, and snowy conditions.

Which One Should You Choose?

As already mentioned, both SPT-1 and SPT-2 wires offer the same maximum amperage. The difference between these two wires is simply their insulation thickness.

However, with an insulation thickness of 50%, SPT-2 cables seem better for appliances requiring about 7-amps.

SPT-2 wires would also be preferable when used with appliances that must sit outdoors for longer than 90 days. Their thicker insulation would offer better protection against long-term exposure to ultraviolet (UV) rays from the sun.

Lastly, SPT-2 wires would be more suitable for use in extremely cold climates. As we’ve already hinted, this has a lot to do with the fact that SPT-2 wires don’t break so easily.

Final Word

There goes our guide to SPT-1 and SPT-2 wires. Hopefully, you can bookmark this post the next time you shop for these two wire types for your everyday household appliances.