How to Select a Power Strip Based on Wire Gauge

If you are looking for a power strip for your smart devices, most likely you would pay attention to whether it has built-in USB ports or the specifications like input, output, and the rated power, etc. Sometimes you will also take a look at the cord length if you are looking to an extension cord instead of an outlet extender. Therefore, despite the key specifications listed above, when it comes to the cord, is there any other feature we need to check besides length? Wire Gauge! It is true that wire gauge plays an important role for a power cord.

Wire gauges are broadly divided into two standards. One is the American wire gauge (AWG), which is prevalent in North America and used to some extent in over 65 countries, with a market share of about 30% of all power and control wires and cables. The other is British Standard Wire Gauge (often abbreviated to Standard Wire Gauge or SWG), also known as the Imperial Wire Gauge or British Standard Gauge. Use of SWG sizes has fallen greatly in popularity, but they are still used as a measure of thickness in guitar strings and some electrical wire.

The term ‘gauge’ is used to define the diameter of the wire, which determine the amount of current a wire can safely handle. The amount of current that a wire can carry depends on a few different factors, for example the composition of the wire, wire length, and condition of the wire. In general, thicker wire can carry more current.

There are two main reasons for choosing the right size wire for the load. The first reason is to ensure that the cable can safely carry the maximum load current without overheating, which may present a fire hazard or cause the insulation to degrade. The second reason is to minimize the IR voltage drop across the cable. Both of these phenomena have a direct effect on the quality of power delivered to and from the power source and corresponding loads.

The thickness of the wires inside an extension cord dictate how much power it can safely carry. Thicker wires can carry more power over longer distances. Any cord should meet the minimum requirements to run low-power gears like light, battery charger, etc. But the minimum won’t do if you want to run power tools like drill, saw, or wet/dry vacs safely and at peak power. Cord thickness in the US is generally listed in terms of gauge, or AWG. Larger numbers mean smaller wires, which in turn means it can carry less power.

In addition, the resistance of the wire also depends on the cable thickness and cable length. A longer thinner wire will have higher resistance than a shorter thicker wire of the same structure. An ideal wire should have the lowest resistance possible. To get the best energy transfer a thicker wire such as a 12-gauge wire would be preferred over an 18-gauge thinner wire.

By the way, the ability of a wire to carry current, also called its ampacity, decreases as the ambient temperature increases. And a stranded wire is more flexible, easier to route, can withstand vibration and flexing than solid wire

In one word, if you are searching a power strip for your low-power gears like phone chargers, lamps, or maybe a wireless speaker, which mostly used indoors, despite the key specifications, look for those with a power cord in the range of 14~18 AWG as these are the most recommended wire gauges for the indoor power strips with the best performance and price. If it comes with a 45°angled flat plug, that is even better as this kind of plug gives you easier access to wall outlets hidden behind furniture, such as bed or sofa.