Problems using long extension cords
All extension cords are not created equal. Although it may seem logical to buy a very long extension cord to use for a variety of purposes in different places, the smart move is to buy various lengths of extension cord, and use the one that is just long enough to get the job accomplished.
Using a longer cord than necessary can lead to several problems.
Lack of Voltage
When it comes to voltage, the gauge of the wire is an important factor in selecting an extension cord for a particular use. The lower the gauge, the thicker the wire and the better it can deliver the proper voltage to the object you are supplying. But gauge is not the only factor to consider. The length of the cord also affects voltage.
As the current from an outlet delivers voltage further from the source through an extension cord, the level of the voltage drops off. Using a very long extension cord means that the object receives a considerably weaker voltage than it would if it were plugged into a short cord or plugged directly into the wall. Power tools are an example of electrical devices that require a lot of voltage to perform the job properly. If the tools are connected to a long extension cord, the level of voltage may make them inadequate.
Tool Motor Overheating
When a tool does not receive enough voltage to the motor, the motor may overheat. Overheating can lead to damage to the motor. Since a long extension cord gradually loses its ability to supply voltage, this loss can lead to overheating in tools and potentially ruin expensive devices that might be saved by simply using a shorter connection to the power supply.
If the situation makes completing the task impossible without using a long extension cord, use the thickest, lowest gauge extension cord you can find. A 12-gauge cord will carry considerably more power than a 16-gauge cord and could make enough of a difference to save the tool's motor from damage and overheating.
When a cord of appropriate length can't be found around the house, daisy chain the extension cords. People will take the short cut by connecting two or more extension cords together to form a longer one and may even use a surge protector as part of the chain. Don't do that. If you have daisy chained extension cords or surge protectors in a place of business, understand that this is a violation of OSHA standards as well as inconsistent with the National Electrical Code, according to the United States Office of Compliance. Daisy chaining extension cords can cause overloads, may lead to device failure and can potentially cause fires.