Letters to the Editor
Good Standard Practice: Use 12 Gauge Cords of 100 Feet or Less
A recent e-mail issue of Nation’s Building News contains an article about how one could safely tie two (or more) drop cords together (“Locking Electrical Cords Together,” May 9). This is not a safe practice and several factors need to be understood.
- Drop cords come in many configurations and it is very common to find cords on a job site that are made with 14 or 16 gauge wire, and cords that may even lack a UL label. I always suggest the purchase and use of quality drop cords with at least 12 gauge wires (conductors) because of voltage drop. The larger the gauge of the conductor, the less the resistance of the cord’s conductors and the less drop in voltage at the end of the cord. A 16 gauge cord should never be used for distances in excess of 25 feet as a rule of thumb — if it is used at all.
- Voltage drop is caused by the resistance of the conductors as the electricity travels down its length. The drop in voltage causes the electric motor in the tool ― or the elements in a heat gun, etc. ― to work harder and thus diminishes the life of the tool. An electrician could perform the calculation to determine the voltage drop on a particular cord length/gauge, but a good idea is to use 12 gauge cords in lengths of 100 feet or less as a standard practice.
- The resistance of a conductor also creates heat — can lead to the melting of a cord’s conductors, which can lead to a fire or electrical shock, which can lead to death and/or lawsuits.
Please pass this information along to your readers so you do not encourage bad working practices.
J.H. Bowman Electric Co., Inc.
Robert Matuga, NAHB director of Labor, Safety and Health, recommends that, if drop cords must be secured together, they should be secured with non-conductive materials such as twine, rope or electrical tape or by tying a knot.