As part of their emergency planning, many people are opting to use a portable electric generator if a power failure occurs. These handy devices can keep your business operational in a blackout situation. But they can also be dangerous — many people are killed each year through misuse, improper installation and poor maintenance of portable generators. Carbon monoxide poisoning, electrocution and fires are the most common dangers associated with generators.
To ensure the safety of you and your personnel, follow these recommendations when operating a portable electric generator.
Never plug directly into a building outlet. Directly connected generators can “backfeed” onto the power lines connected to your building. Utility transformers can then step up or magnify this backfeed into thousands of volts, injuring neighbors or utility workers. This backfeed can also cause your generator to catch fire or explode when the line power is restored. Connect individual appliances that you wish to power directly to the outlet of the generator or connect these appliances to the generator with the appropriate outdoor-rated power cord.
If you wish to connect a generator directly into the wiring of your home or business, a transfer switch must first be installed to isolate your building from utility power. A manual or automatic transfer switch can be wired directly into your distribution system so you can use your home power receptacles rather than plugging into the generator.
Avoid overloading the generator. Overloading your generator can seriously damage appliances and electronics. Know your generator’s limits and adhere to them. Set priorities on what you use the generator for.
Never use a generator indoors. Generators use a standard gasoline engine that emits deadly carbon monoxide; therefore, they should never be used inside any type of building.
Minimize the risk of electrocution. Generators should be kept dry and properly grounded. Don’t touch a generator if you are wet or are standing in water or on damp ground. Ground fault interruption devices that are built into wall outlets should be used to protect main household circuits. These circuits trip off if the current surges.
Use the proper power cords. Plug individual appliances into the generator using heavy-duty, outdoor-rated cords with a wire gauge adequate for the appliance load. Overloaded cords can cause fires or equipment damage. Don’t use extension cords with exposed wires or worn casings. Make sure the cords from the generator are arranged so they don’t cause a tripping hazard. Never run cords under rugs where heat might build up or cord damage may go unnoticed.
Read and adhere to the manufacturer’s safety and operation manuals. Carefully read and observe all instructions in your portable electric generator’s owner’s manual. These instructions give you the proper procedures for starting, stopping, installing and maintaining your generator.
Do not store fuel indoors or try to refuel a generator while it’s running. Gasoline should be stored outside of living areas in properly labeled and approved containers. It should not be stored in a garage if a fuel-burning appliance is housed there. Highly flammable vapors from gasoline can drift along the ground and be ignited by pilot lights or electric arcs caused by turning on an electrical appliance. Avoid spilling fuel on hot components. Extinguish all flames or cigarettes when handling gasoline or any other combustible material. Always have a fully charged, approved fire extinguisher near the generator, and never refuel a generator while it’s running.
When purchasing a generator, be sure to buy one that suits your needs. Selecting the proper wattage of a generator involves more than simply adding up the wattage of lights and appliances you wish to operate. You need to be sure the generator can handle start-up requirements for many motorized items. Don’t allow your generator to be overwhelmed by start-up power needs or the total running load of the appliances or other uses you attach to it. A furnace fan, for example, may need over 2,000 watts to start. In addition, if you plan to hook up large appliances, such as compressors, welders, well pumps or dryers, make sure your generator is rated for 240-volt as well as 120-volt loads.
Purchasing a portable generator for home or business use can range from $450 to $4,500, depending on manufacturer, output, design and features. The higher the output, the more sophisticated the design, and the more features a generator provides, the more the generator will cost. You must also add in the cost of all accessories and installation. A transfer switch, for example, can cost an average of $150 for a light-duty, 30-amp model, and a heavy-duty power cable can cost from $75 to $150. Professional installation can cost from $400 to $800, depending on travel time for the contractor, the type of transfer switch and the distance of the transfer switch from the main service panel.