Extension Cord Selection Guide: Factors to Consider

Types of Electrical Extension Cords

The first step when choosing an extension cord is to consider the weather conditions. If the conditions are wet, sunny, cold, or harsh, you will need a durable, heavy-duty cord that can withstand wear and tear.

Extension Cord Code Designations

The type of cable can help you choose the best extension cord for different uses. The designation letters give a clearer picture of what a cord can do.

The outer layer of an extension cord (i.e. jacket) includes a designation that is a sequence of letters, each of which has a specific meaning. Knowing these letter designations will help you determine the right cord for your application.

Things to Consider when Selecting an Extension Cord

To find the right extension cord, you must also understand the importance of gauge ratings, amperage, and cord length. These three factors combined are crucial in ensuring the cord matches the job.

Extension Cord Gauge Rating

Any extension cord you buy will have an American Wire Gauge (AWG) rating. This is a standard system for measuring electrical wire. Typically, the AWG rating will consist of the gauge and the number of conducting wires. For example, a 12/3 extension cord rating contains 12-gauge wire and three conductors.

For extension cord gauge ratings, lower numbers indicate a thicker wire and higher capacity. The lower the number, the more electrical current an extension cord can deliver. The higher the number of conductors, the less likely the extension cable is to overheat. Usually, power extenders are available with one or three conductors.

Extension Cord Amperage

The amperage rating of a cord determines how much power, or electrical current, it can safely carry. Most everyday power needs can be met with 15 and 20-amp cords. However, high-amperage appliances may require higher-rated cords. You should use an extension cord with equal or higher amperage than the equipment needs.

Extension Cord Length

The length of an extension cord wire will determine its power capacity. The electrical resistance of a cable increases with each extra foot added. In other words, a long cord with higher electrical resistance can generate less power.

When selecting an extension cord for high-powered equipment, choose a short, heavy-duty power cord. If your task requires a longer extension cable, make sure the gauge rating is lower. This ensures the same amount of electrical current and energy as a shorter cable.

Other Extension Cord
Selection Considerations

• Two vs. three-prong configuration. You can use a three-prong plug with two or three-prong devices. A three-prong configuration reduces the possibility of electric shocks and fires. On the other hand, you can only use a two-prong plug with a two-prong device.
• Ground Fault Circuit Interrupter (GFCI). GFCI offers built-in protection that cuts power in the event of a ground fault and is highly recommended for damp environments.
• Light indicator. See when a cord is powered with a light indicator.

User Safety Tips
 

• If possible, store extension cords in a dry and cool location and never use the cord if wet.
• Use cable protectors where vehicles may drive over the cord and where it could be a tripping hazard for workers.
• Help prevent electrical surges from damaging expensive equipment with a surge protector.
• Do not plug extension cords into one another; only use one cord per device.
• Always check the extension cord for signs of damage before use.
• Do not nail or staple extension cords to any surface. Instead, use holders and hangers to organize extension cords.
• Do not use indoor extension cords outdoors, as they are not weather-resistant.
• Check the maximum amperage of an extension cord before using it. This helps prevent connecting a device that uses too much current, which may cause the cable to overheat.