Choosing a Backup Generator

Article Tools

Image Gallery

Print

E-mail

Comments

RSS

GENERATOR COMPONENTS

Most generators have four primary parts: an engine that provides the mechanical energy; an alternator that converts the mechanical energy into electricity; an output/control panel that houses electrical outlets, circuit breakers and switches; and a frame to hold all the components together. In the case of a gasoline- or diesel-powered generator, a fuel tank is attached. This combined unit is referred to as a generator set or "genset."

The most common residential backup gensets use gasoline engines, but this category includes a wide range of generator options. Cheaper generators have single-cylinder, air-cooled engines. Higher-quality units have multiple-cylinder, liquid-cooled engines that provide a steadier operating temperature and substantially less engine noise due to the sound-reducing qualities of the water jacket. An engine that has overhead valves (OHV) is easier to start, runs quieter, lasts longer and produces less emissions than non-OHV engines.

Unfortunately, OHV engines cost more. Another technical issue to consider is whether the engine has a cast iron sleeve (CIS) in the cylinder. This sleeve reduces the friction that causes cylinder wear, prolonging the engine's life. Both these features (OHV and CIS) are important if your generator will b e running frequently or for long periods, especially if you plan to use it to back up a renewable energy system.

Engine speed is another factor that relates to how long a genset will last. Aircooled engines that run at 1,800 revolutions per minute (rpm) normally last longer than those that operate at 3,600 rpm. But some manufacturers offer overhead camshaft, liquid-cooled engines that run at 3,600 rpm and that will outlast most 1,800-rpm models. To find the best buy and the best engine to meet your needs, do your homework and ask a lot of questions.

Because alternators are what generate electricity in the engine, it's equally important to choose one that is built to last. All-metal construction is preferable to plastic, which can crack or warp, causing the internal parts to wear or break. Alternators that use ball bearings rather than needle bearings in their construction should have a longer life span, too. Another important feature to look for is a "brushless" design, which requires less maintenance and generates "cleaner" power for electronic devices such as computers.

RSS | Comments | E-mail | Print