An emergency source of power is important for any home or farm during an extended outage. They are essential for things like sump pumps, emergency heat, and special medical needs for home-bound residents; for ventilation and water needs in a livestock operation. A standby electric generator can prevent costly losses during a power failure.
Types of generators
Standby generators come in either engine-driven or tractor-driven models; either stationary or portable. Engine-driven units are made with either manual or automatic start and are fueled by gasoline, LP (bottled) gas, natural gas or diesel.
Power-take-off (PTO) generators (tractor-driven) are usually mounted on a trailer and cost about half as much as engine-driven units. This type of system is very common on most farms where tractors are common. Safety is always a concern around PTO-drives.
Generators must provide the same type of power at the same voltage and frequency as that which is supplied by the utility for the location at which it’s used. This is usually 120/240 volt, single phase, 60-cycle alternating current (AC). An air-cooled engine often will be used for generators up to 15 kilowatts. Generators larger than 15 kilowatts usually require a liquid-cooled engine. An engine capacity of 2 – 2¼ hp is typical for each 1,000 watts of generator output.
Sizes of generators
A full-load system will handle the entire electric load being served. Automatic, engine-driven, full-load systems will begin to furnish power within seconds after power is lost. Smaller and less expensive partial-load systems may be enough to handle essential equipment during an emergency. A partial-load generator will only supply the most essential equipment operating at any given time.
Wiring and equipment must be installed in accordance with the National Electrical Code, local ordinances and CCEC requirements (see http://www.kwh.com). Proper equipment is essential for disconnecting the generator from public utility lines. CCEC requires the installation of a double-pole double-throw transfer switch or its equivalent.
An automatic standby generator should start automatically when electric power is lost, and automatically stop and shut down when power has been restored. When using either an engine-driven generator with a manual start or a tractor-driven unit, follow this procedure when power fails:
1. Call your power supplier and advise them of the conditions.
2. Turn off or disconnect all electrical equipment.
3. Position the tractor or engine with the generator so as to allow sufficient room for connecting the electrical wires to the appropriate equipment.