A 20-amp extension cord is one of the most common electrical cables in both residential and commercial settings. It’s also one of the most commonly misunderstood.
So, we’ve taken the liberty of putting together an informative piece on 20-amp extension cords. Here’s everything to know about these electrical cables, including how to choose and safely use them.
What Is A 20-Amp Extension Cord?
The best way to understand a 20-amp extension cord is to break the phrase down into two parts – “20 amp” and “extension cord” – and define each term separately.
An extension cord is a length of flexible electrical wire used for powering electrical devices. It’s also known in other jurisdictions as an extension cable, extension lead, power extender, or drop lead.
Extension cords have a plug on one end, with the other end featuring one or several sockets. The sockets are usually of the same type as the plug. In other words, an extension cable with a three-pronged plug would equally come with a three-holed socket.
Amp (short for amperage) is an electrical jargon that appears on many electrical cables and appliances. It refers to the amount of current that can safely flow through an electrical circuit.
Now, a 20 amp extension cord is basically a power extender rated for 20 amperes. These cables let you connect electrical equipment rated for up to 20 amperes.
Features to Look for In 20-Amp Extension Cords
Extension cords rated for 20 amperes are remarkably effective at handling electrical current. However, their overall efficacy depends on other specifications.
Below are the common features to look for when shopping for 20-amp extension cords;
1. NEMA Ratings
The National Electrical Manufacturers Association (NEMA) and the International Electrotechnical Commission (IEC) are the two main organizations that rate electrical equipment.
NEMA standards generally apply to cords and receptacles used in North America, whereas the IEC guidelines are more global.
However, NEMA extension cords are considerably more resilient against short circuits than their IEC-graded counterparts. While IEC drop cords tend to be more compact and affordable, they respond dramatically to circuit overloads.
2. Gauge
The gauge of an extension cord refers to the cable’s thickness. It denotes the diameter of the wire’s conductor material, exclusive of the outer insulation.
The conventional wisdom is to pick 20-amp extension cords with a gauge rating of at least 12 or 10 AWG. A higher-gauge rating translates to better current handling abilities.
For clarity’s sake, note that higher-gauge wires are represented by smaller AWG ratings. That means a 10 or 12 AWG 20-amp power extender is more resilient than a 14, 16, or 16-gauge cord.
3. Length
20-amp extension cords are available in different lengths. They can be as short as 5 feet or as long as 100 feet.
Longer extension cables are suitable for powering electrical devices located further from the main outlet. They’re ideal for outdoor use, such as in lawn or construction sites.
On the flip side, longer cords have more resistance. That makes them less efficient at handling electrical current.
So, unless you’re working outdoors, you’ll be better off with a shorter 20-amp extension cord. Insist on cables no longer than 15 feet.
4. Safety Features
Electricity can be notoriously unpredictable. While a 20-amp extension cord is already fairly resistant to current overloads, it’s best to choose a wire that comes with other safety features like GFCI protection.
GFCI (ground-fault circuit interrupter) is a safety mechanism on electrical cables designed to break the circuit during power overloads. It works by automatically shutting off electricity supply when a ground fault occurs.
Another key safety feature to look out for in 20-amp extension cords is a weatherproof, abrasion resistant jacket.
How to Safely Use 20 Amp Extension Cords
A 20-amp extension cord is suitable for use with 20-amp receptacles.
20-amp receptacles are easily identifiable by their shape. These three-pronged outlets have two vertical and one roundish slot.
One of the vertical slots is slightly inclined into what looks like a sideways “T” or a winking human face.
20-amp outlets are commonly confused with 15-amp ones. But while both receptacles are three-pronged, none of the two vertical slots in a 15-amp receptacle is slanted. So, the outlet resembles a human face without the wink.
Due to these physical differences, it’s best to use a 20-amp extension cord with a 20-amp receptacle.
In terms of specific appliances, a 20-amp extension cord can power different types of heavy-duty electrical equipment depending on whether it’s a 12-gauge or 10-gauge cable. Noteworthy examples include;
- Kitchen appliances like refrigerators, freezers, toasters, and ovens
- Laundry equipment like washing machines and dryers
- Outdoor tools like lawnmowers and grinders
It’s also important to use a 20-amp extension cord with a compatible circuit breaker system.
If your property is installed with a 20-amp circuit breaker and 20-amp outlets, it’s great to know that you can safely connect both 20-amp and 15-amp extension cords to the receptacles. However, it’s best to use a 20-amp power extender rated for 12 AWG and not 10.
Although a 10 AWG drop lead has a thicker diameter, hence generally more reliable, you could run into certain difficulties associated with using thicker conductors. Only opt for a 10-gauge 20-amp extension cord if using it with an equally rated electrical appliance.
Final Word
The efficiency of a 20-amp extension cord, as with most electrical components, depends primarily on safe usage. Feel free to bookmark this article as your guide for choosing and using 20-amp power extenders.
