Don’t buy the cheapest extension cord you can find. Here is a good explanation of what you should look for (from ChainSawJournal):
Typically, outdoor extension cords will have a number on the packaging or in the listing that looks like this: 12/3. The “12” represents the gauge wire rating (or wire diameter), and the “3” means it has three wires (or conductors) inside. Sometimes the wire gauge might be referred to in a more formal manner, such as, the American Wire Gauge (AWG). The AWG system has been used since 1857.
Whoever came up with gauge ratings made things very confusing for the average consumer. The lower the gauge number the thicker the conducting wire(s) inside the extension cord and thus the greater flow of electricity. A wire’s thickness directly affects the amount of current (or amps) it can carry. Choosing a slightly lower gauge (thicker wires) will ensure electricity flows freely through the outdoor extension cord.
So, you’re better off with a slightly smaller gauge (thicker wire, greater electricity flow) than a slightly larger gauge (thinner wire, less electricity). If you’ve ever had an outdoor extension cord that feels hot, it’s because the conducting wire inside was too thin (high gauge) and electricity couldn’t flow freely due to resistance from an inadequate wire that couldn’t handle the full current for your chainsaw, or other power tool or device.
Important points to follow
- Only buy an outdoor extension cord with the UL symbol (or the recognized symbol from the country you live in). This indicates that the cord has been tested by Underwriters Laboratories and has received their official stamp of approval.
- Exposure to outdoor conditions can cause cords to deteriorate over time, so store your extension cords inside when you’re not using them.
- Only use extension cords marked “For Outdoor Use”. It should have a “W” designation. Quality outdoor extension cords have connectors molded onto them to prevent moisture from seeping in, and outer coatings that are designed to withstand damage from being dragged along the ground.
- Buy only the length you need. The shorter the better.
- Never plug an extension cord into another to extend your reach. Just use one.
- Never use a damaged cord. Whether it’s frayed, cut, or flattened. Toss it out and buy a new one.
- Keep the cord away from any moving parts of your power tool, including, chains, blades and anything else that spins, rotates or cuts.
- Always unplug an extension cord when not in use. The cord continues to conduct electricity while plugged in, which makes it a safety hazard if kids or pets chew on the cord or stick sharp metal objects into the exposed end. Serious injury could occur and it’s easily avoidable. Just unplug and store indoors