How Does an Extension Cord Work?

Extension Cords: More Complicated Than You Think

• There are many extension cords on the market, and it's easy to think that they all do the same thing. In a way, they do; extension cords transmit electricity through an insulated line to electrical appliances and equipment. However, there are different types of cords that range from light household use to heavy-duty industrial strength.
  
  Cords these days actually use lots of technology to keep people safe and appliances functioning in a healthy manner. For instance, cords are now produced with polarized sockets that accommodate the asymmetrically-sized plugs that are used on all modern appliances. Polarized plugs prevent electrocution by connecting to a ground wire that protects users from accidental shocks by exposed, hot parts. Cords may also contain circuit breakers that will cut off power if there's a power surge or overheating occurs.
  
  

How Do These Cords Work?

• According to Ask The Builder's Tim Carter, electrical cords are made by encasing conducting wire (usually copper) of differing gauge in rubber. These wires conduct voltage from a wall socket through the cord's prong end to the socket end. Along the way, it keeps the circuit flowing through whatever appliance happens to be attached.
  
  It's important to note that cord length, wire gauge and distance all contribute to the quality of electricity that an appliance happens to receive. "You will often see numbers like 16, 14 or 12 gauge on extension cord wrappers... a 12-gauge wire can carry significantly more power than a 16-gauge wire," Carter states. The smaller number gauges have more copper than the thicker ones, and are the better choice for heavy-duty tasks.
  
  

Extension Cord Buying Tips

• Due to friction and loss of energy, longer cords create less usable energy that shorter ones do. Tools that pull a lot of current need the shortest cord possible. Otherwise, the power center of the tool or appliance will strain to get the power needed, and may burn out prematurely.
  
  Shop for a good assortment of size ranges and gauges. Inside of the house, thin cords may be decent. However, it pays to invest in something with a good gauge that consistently conducts current. Wattage fluctuations can kill machinery over time.
  
  If you're going to be using tools outside of the house, purchase a cord specially made for outdoor use; it'll be more insulated than a normal cord, and is safer against possible wetness from hoses or rain. Look for something called a "ground fault circuit breaker" when buying your cord to ensure that you get the most up-to-date safety device on your cord.