Monday , May 20 2024

Extension Leads: Choosing the Right Cord for Commercial and Residential Use

Are you in need of an extension cord? You can probably go down to your local brick and mortar store and find one that’s suitable for your application. However, those you’ll find online are generally more affordable and better quality, as long as you can afford to wait a day or two. If you only need one cord, you’ll have to focus on several different factors to make sure you choose the right one. It’s particularly important to know whether you need an indoor or outdoor one. Regardless, there are a few guidelines you should follow to ensure you make the right purchase.

Cable Length

white extension lead

When you’re considering the length of extension leads, give yourself some extra room for error and buy a lead that’s slightly longer. Longer leads are more convenient and safer. It can get annoying if the lead barely reaches your desired spot. You should avoid daisy-chaining extension leads. The length of multiple leads connected to one another without thick wires to make up for their distance can add electrical resistance between the socket and whatever it is you’re trying to feed power. The increased resistance can result in voltage drops, making equipment like saws, drills and vacuums operate at lower power. Additionally, the added resistance can lead to extra heat build-up, increasing the risk of leads melting and starting a fire. Even if you ignore all the safety risks associated with shorter cords, there’s another reason to get a longer cord than you currently need – you might use it for your next project.

Cable Thickness

Besides length, the thickness of extension leads dictates how much power they can carry safely. Thicker wires are capable of carrying more power over longer distances. While any lead will probably meet the minimum requirement on providing power to low-power equipment like stereos, battery chargers and lights, they won’t be able to operate power tools like saws, drills, etc. Cord thickness is expressed in gauge, or AWG. The larger the gauge number, the smaller the wire, meaning less power. You can find the gauge information on the lead’s specification sheet, or on the lead itself.

Amperage Capability

plugging in an extension lead

If you’re confused by the cord thickness and length specifications, you should take a look at the amp rating. For most applications, you want a cord rated at least 15A. If the cord doesn’t have its maximum amperage listed, you should avoid it. That way, you ensure that you can plug virtually anything on it and it will operate safely. The most common breakers and fuses are also rated 15A, so if the cord is pushed past its limits, power will be cut off. For residential use, you won’t have to worry about the voltage rating. For industrial use, you’ll want a cord rated at least 230-240V.


Some cords are more flexible than others, especially when used in cold weather conditions. Flexible cords are recommended when you need to stretch them out across your working environment, and they’re easier to coil and store. Furthermore, they’re easier to use in tight spaces. When the cords are wrapped in their package, it’s difficult to distinguish their flexibility. So, you’ll have to unspool them to get an idea of their flexibility. When shopping online, though, that’s not an option, so you should look at its temperature rating. The lower the temperature rating, the better.

Avoid Multi-Outlet End Cords

Multi-Outlet End Cords on fire

You might consider getting an extension lead with a few outlets at the end which are commonly known as banana taps. However, if you’re looking for a durable lead that’s capable of running heavy-duty equipment, work lights, tools and other demanding devices, they should be avoided, simply because they’re easy to overload. For instance, 15A cords can easily handle a power drill, but if you also plug work lights onto them, every time you use the power drill, you can overload the cord. If the circuit has a 15A breaker, it will trip immediately when you try running the drill, making work impossible. That being said if something requires serious power, and for general-purpose leads that you want to use for a long time, stick to cords with single outlets.

Indoor Cords

If you’re going to use the cords for casual, residential purposes, such as hooking a phone charger or a nightlamp, you probably don’t need a thick, heavy-duty extension cord. You can get a conventional indoor cord from any brick and mortar store and use it just fine, as long as you’re aware of its limitations. Plugging a small fan onto it will be fine, but powering an air conditioner is out of the question. The most important thing to pay attention to when buying indoor cords is that UL doesn’t allow extension leads to be used in permanent installations. This means that you shouldn’t use them instead of real electrical cables to wire outlets.