Selecting a Size
Before buying, you'll need to determine how much power you'll require from a generator, which is rated in watts.

• Decide which appliances you can't live without. Refrigerators, microwaves, furnace fans, lights, televisions, and radios head many people's necessity lists.
• Calculate how much electricity those items need by checking each product's faceplate or owner's manual.
• Find the total wattage of all your necessary appliances. The generator you buy needs to deliver at least that much wattage--and preferably a bit more.

Warning: Appliances with motors (such as freezers, refrigerators, and furnace fans) require additional wattage to start. A 700-watt refrigerator, for instance, could require an additional 2,200 watts when firing up. If you plan to start a group of motors simultaneously, you'll need a generator with the capacity to supply the necessary starting current for the total wattage. Without sufficient starting power, motors can overheat, burn out, or trip the generator's circuit breaker.

Noise
Earplugs, anyone? With generators, noise is an issue. Some purr, while others roar. If peace and quiet is a priority, consider the generator's noise level, listed in decibels.

• The low end of the noise range measures 50-60 decibels.
• If a generator rattles at 80 decibels, you might have to raise your voice to be heard. That may be fine at a job site, but frustrating in a tent.

Weight
How portable is it? Some generators come with wheels and move easily, others have handles and must be lugged around. So check the weight of the model you are considering, and remember that a generator without wheels can be awkward, if not impossible, to carry very far.

Fuel Tank vs. Run Time
Before buying, find out how long the generator can run on a full tank of gas. As a rule, the more powerful the generator, the worse the gas mileage. Between models, the run time can range from 2 to 10 hours. Fuel tank size varies, too, so check the tank capacity. This will give you an idea of how often you'll have to stomp out in the night, uncap the gas can, and refill the tank. Of course, you face a tradeoff: a bigger fuel tank guarantees a bulkier, heavier generator.

Start Your Engines
When choosing a generator, consider the starting device--recoil or electric?

• The recoil method, featured on most inexpensive models, starts with a pull or two, much like a lawn mower.
• If you want the ease of flipping a switch, then a more expensive model, with an electric starter, is the way to go.

Beyond Y2K
Generators were hot Y2K sellers--but their usefulness didn't vanish with the (calm, as it turns out) dawning of the new millennium. With the right generator, you can make your power portable. Film crews, hunters, and campers have long relied on generators to power their sites and equipment. In addition, windstorms, ice storms, earthquakes, blizzards, and hurricanes--things far less predictable than Y2K was--all threaten to leave us in the dark without warning. But with a generator waiting in the wings, if the lights go out, you'll be prepared.

Safety
In the wrong hands, a generator is a dangerous thing. Even the smallest generator produces electricity at levels high enough to cause property damage, injury, and death. Always make certain your manufacturer provides clear safety and user guidelines.

Other Information:

Choosing the right Generator or Generators

Once you've decided to purchase a generator set, there are several considerations you must keep in mind when choosing which set to buy, where to install it and how to install it.

This guide will help you make informed decisions during the selection process. Choosing the right machine is not difficult if you take the time to analyze your requirements carefully.

You will also need to know a few terms and have a basic understanding of the different types of generator sets and their operating principles.

Installation requires expert assistance and a strict adherence to local codes and regulations. We recommend that you have a contractor do your installation.

STAND-BY OR PRIME?
The first determination you will need to make is whether you will require stand-by or prime power. Simply stated, prime power is required when you have no other source of power. A stand-by set is a backup to normal utility power

GENERATOR TYPES & FEATURES
Generator sets produce either single or three phase power. Choose a single phase set if you do not have any motors above five horsepower. Three-phase power is better for motor starting and running. Most homeowners will require single phase whereas industrial or commercial applications usually require three phase power. Three phase generators are set up to produce 120/208 or 277/480 volts. Single-phase sets are 120 or 120/240. Use the low voltage to run domestic appliances and the high voltage for your motors, heaters, stoves and dryers.

GAS OR DIESEL?
We recommend diesels due to their longevity and lower operating costs. Today’s modern diesels are quiet and normally require much less maintenance than comparably sized gas (natural gas or propane) units. Fuel costs per kW produced with diesels is normally thirty to fifty percent less than gas units.

1800 rpm water cooled diesel units operate on average 12-30,000 hours before major maintenance is required. 1800 rpm water cooled gas units normally operate 6-10,000 hours because they are built on a lighter duty gasoline engine block.

3600 rpm air-cooled gas units are normally replaced – not overhauled at 500 to 1500 hours.

Because the gas units burn hotter (higher btu of the fuel) you will see significantly shorter lives than the diesel units.

OPERATING SPEED
Electric equipment is designed to use power with a fixed frequency: 60 Hertz (Hz) in the United States and Canada, 50 Hertz in Europe and Australia. The frequency output of a generator depends on a fixed engine speed. To produce 60 Hz electricity, most engines operate at 1800 or 3600 RPM. Each has its advantages and drawbacks. 1800 RPM, four pole sets are the most common and least expensive. They offer the best balance of noise, efficiency, cost and engine life. 3600 RPM, two pole sets are smaller and lightweight, best suited for portable, light-duty applications.

In simple terms it’s like operating your car at 90 mph, versus 45mph – at 45mph your car will last longer, is quieter, less maintenance and longer life. Most 3600 rpm units are twin cylinder air cooled lawn mower engines, while the water cooled 1800 rpm units are comparable to those found in forklift and tractor engines…the 1800 rpm water cooled units will last longer, offer less maintenance problems and be more fuel efficient.

FEATURES & BENEFITS TO LOOK FOR
ENGINE
Engine block. For long life and quiet operation we recommend four cycle, liquid cooled, industrial duty diesel engines.

Air or liquid cooling. Air-cooled engines require a tremendous amount of air and may require ducting. They're noisy too. Liquid cooling offers quieter operation and more even temperature control.

Intake and exhaust. Time and money savers include a large, integral air cleaner with replaceable filter element and a residential muffler, which is built into the exhaust manifold. This saves the need for an additional muffler.

The lubrication system should have a full flow, spin-on oil filter with bypass.

Major brand of engine – We do not recommend you purchase a Chinese built unit or off brand engine, you will not be able to obtain the necessary follow-on parts and service support available with reputable manufacturers!

DC electrical system. Standard 12 volt system should include:

Starter motor and battery charging alternator with a solid state voltage regulator

Diesel units should come with a pre-heat switch and start/stop switch

Safety shutdown system to protect the engine in case of oil pressure loss, generator overspeed or overcrank and high water temperature

DC system circuit breaker.

GENERATOR END
AC generator should have a 4-pole revolving field. An automatic voltage regulator (AVR) will provide “clean” power. Normal utility power is +/- 5% voltage regulation; some 1800-rpm models are even better +/- 2%!

Lifetime lubricated bearing – some less expensive units – are not supplied with these bearings…they often require complete disassembly every two or three years for bearing replacement.

ENGINE ACCESSORIES AND CONTROLS
Upon determining the generator size you will need, make a list of optional and installation equipment you require. For noise abatement, we recommend a residential (not industrial grade) muffler. A good primary fuel filter/water separator is a must to protect your engine's fuel system. Stand-by sets may require a block heater to keep the coolant/water mix at an adequate temperature for easier starting.

AC SWITCHGEAR AND CONTROLS
Switchgear can be as simple or complex as you want or can afford. Of course, as complexity increases, so does cost. Balance and a good electrical advisor are the keys here. The diagrams at right illustrate basic configurations for prime power and stand-by systems. All generator systems require a circuit breaker and a distribution panel. The circuit breaker protects the generator set from short circuit and unbalanced electrical loads. The distribution panel divides and routes the connected loads and includes circuit breakers to protect these loads. Stand-by systems also require a main circuit breaker between the utility source and the transfer panel. The transfer panel switches power from the utility to the gen-set and back so that both aren't on at the same time. Auto-start, auto-transfer systems are available but are costly. Your supplier or contractor can help you determine what you will need.