• Understand Your Generator Options

• Determine What Size Generator You Need

• Install and Maintain Your Generator

• Find Generators on eBay

• Buy Generators With Confidence

Understand Your Generator Options

Understand Your Generator Options

All generators have two main components: A motor that burns fuel (usually propane, natural gas, gasoline, or diesel) to supply power and a generator head that turns power into electricity. Together, the motor and the generator head comprise a standard generator. Generator motors typically use engines from well-known names such as Ford, GM, and Honda to drive the generator heads, which makes it easier to find parts and service than if you buy a no-name brand. Generators come in two basic designs: standby generators and portable generators.

• Standby generators: Standby generators, offering anywhere from 7 kW to several hundred kW, help offset the harmful effects of power outages. Installed permanently as an emergency power source for your business, standby generators are hardwired to your business' electrical system and often get fuel from city gas or propane lines. Safety features can prevent injuries as well as damage to your generator. Quality standby generators will shut down if they lose oil pressure, overheat, or are being worked too hard. They should also have solid steel or aluminum enclosures, good mufflers to reduce noise, and be compliant with all relevant emissions regulations. Standby generators start themselves up around once a week to "exercise" - making sure they're ready when needed. This only takes around 15 minutes, but if noise is a concern, some standby generators have a "low idle exercise" feature that lets them run quieter than usual during this weekly workout.

• Portable generators: Portable generators provide power in remote locations, such as construction sites, for short periods of time. In a pinch, they can also power essential equipment during a power outage. Portable generators tend to be smaller and less expensive than standby generators. They have built-in fuel tanks, which allow them to run anywhere, and standard power outlets that can plug into ordinary extension cords. The smallest gasoline-powered portable generators are less than 1 kW and the largest reach around 15 kW. A sub-class of "towable" power generators — designed to be towed to construction sites — run on diesel fuel and can be 200 kW or more. Portable generators should have large fuel tanks for the best running time, a fuel indicator gauge, and enough receptacles to allow you to plug in all the devices you want to run. Always follow the directions for use supplied with your portable generator. Portable generators produce fumes that can cause serious health problems or death if used indoors.

Fuel your generator

Generators can run on several different types of fuel. Some portable generators and standby generators even come in dual- or tri-fuel configurations, which allow you to switch from natural gas to gasoline or propane by reconnecting a hose.

• Diesel generators: Diesel is a popular choice of fuel for larger, commercial generators. Diesel generators tend to be dependable and somewhat less expensive to operate than generators that run on natural gas or propane, but diesel isn't as clean-burning. You'll need to have diesel fuel delivered and a proper tank to hold the fuel.

• Natural gas and propane generators: Standby generators can run on natural gas or propane. The standby generator connects to utility lines and draws fuel when necessary. Choose between natural gas generators and propane generators based on what's available in your area.

• Gasoline generators: Portable generators commonly run on gasoline and are considered gasoline generators. Gasoline can't be stored for very long, so consider a propane generator if you intent to keep a portable generator around for emergencies.

Cool your generator

Generators need an air cooling or liquid cooling system to prevent overheating. Like any motor, a generator motor creates quite a bit of heat, with faster generators producing more heat than slower generators. Generators made for the US market operate at one of two speeds: 1800 RPM or 3600 RPM. 1800 RPM motors typically last longer and run quieter; 3600 RPM motors are smaller and lighter.

• Air-cooled generators: Air-cooled generators cost less than liquid-cooled generators, but produce more noise and are less efficient. Portable generators are almost always air-cooled, 3600 RPM models. In some cases, you may be able to choose between the two RPM settings - go with 1800 RPM unless portability is important.

• Liquid-cooled generators: Standby generators 20 kW and larger typically run at 1800 RPM and use quiet, dependable, and effective liquid-cooled systems. Liquid-cooled generators typically cost more to purchase and maintain than air-cooled generators.

Look at new generators that have a two-year parts and labor warranty. Make sure you know what the warranty covers: some only cover certain parts of the generator.

Determine What Size Generator You Need

Determine What Size Generator You Need

The electricity created by a generator is measured in voltage and watts. When choosing a generator, first determine your specific voltage needs and then you can pick a generator model that supplies enough wattage for everything you want it to run.

• Generator voltage: Voltage is a measure of the "pressure" of an electric current. In the U.S., standard household current is single phase, 120 volts. Most houses have 120/240v service, meaning they have two 120v circuits that combine to provide 240v for power-hungry appliances such as electric ranges, central air conditioning, and water pumps. Many small businesses use this 120/240v service and can take advantage of 120/240v generators. Larger businesses often have different power needs and use three-phase power, which better runs heavy-duty motors than residential-standard single-phase service. In the U.S., three-phase power usually produces 120/208volts or 277/480 volts and you can find 120/208v generators and 277/480v generators that handle these common voltages. Know what voltages your business uses now so that you can find a generator to match.

• Generator wattage: Wattage measures the "volume" of electricity a generator creates. Wattage requirements increase with each additional appliance or piece of equipment you need a generator to power. The smallest generators produce around 800 watts while large industrial generators can produce 500,000 watts (500 kilowatts, or kW) or more. Small businesses typically require generators that can produce 15 kW to 100 kW.

Before choosing a generator, particularly standby generators, you'll need to decide what equipment you want it to run. The "right" size electric generator provides just enough wattage to operate all your essential equipment. Common devices include refrigerators, freezers, security and access control systems, sump pumps, essential lights, electric gates or overhead doors, ejector pumps, well pumps, and septic systems. Keep in mind that every electronic device you add to the list will increase the wattage you need. While a single light bulb will only add 70 watts, a mid-sized central air conditioner can draw 4000 watts or more.

Limit your choices to those devices that are truly essential during a power outage and you'll keep your total costs down. Too few watts and you can overwork the electric generator, potentially damaging it and anything plugged into it. Too many watts and you'll waste money on the initial generator purchase and on fuel. Accurately determining the watts your equipment requires will help you get a generator that can meet your electrical demands without spending too much. You can spend $400 on a hobbyist generator at a chain hardware store or $40,000 on a massive standby generator. As a very loose rule of thumb, standby generators cost $300 to $500 per kW, installed.

Discover how much wattage your devices require

Always investigate the power needs of the devices your generator will need to support instead of estimating. Although you, or a seller, may be able to come up with a good guess as to what size generator your business might need, you should always total the wattage requirements of your devices before finalizing a buying decision.

• Call an electrician to measure wattage: A qualified electrician can use an ammeter (a device that measures electrical current) to determine exactly how much power each piece of equipment needs. Total the wattage the electrician measures for each device to get your baseline power needs.

• Measure wattage yourself: You could determine how many watts your equipment will draw on your own by doing some research. Most pieces of equipment list their power requirements in their instruction manuals or on their nameplates. The number you want to get to is watts, and as you may remember from high school physics, watts = volts x amps. Many devices list amps at a given voltage, so just do the multiplication to see how many watts they draw.

Electric motors use more power to start than they do to run, which means electronic appliances with significant moving parts — such as fans, pumps, compressors on refrigerators, and air conditions — can use up to three times as more electricity to start as they do to run continuously. Remember to factor in these startup requirements when determining how much wattage you need from a generator. Luckily, multiple devices rarely start up at exactly the same time so you'll only need to add enough power to your wattage needs for the device with the biggest startup requirements.

Figure out which equipment has the largest difference between running load and startup load. Then add that number to your total equipment running load to determine your overall wattage requirement. Plan on purchasing a generator rated for a capacity around 20% higher than your requirements. The additional capacity can help you avoid overworking your generator, gives you room to add a few small devices, and can help extend the lifespan of the generator.

Make sure you're comparing the rated capacity of various models, not maximum capacity. An electric generator can deliver its maximum capacity for no more than 30 minutes before starting to overheat. Rated capacity is the level of power a generator can deliver on an ongoing basis, usually around 90% of the maximum power.

Install and Maintain Your Generator

Install and Maintain Your Generator

Get to know exactly what the installation of your generator will involve before committing to a purchase. Then choose qualified electricians and plumbers, experienced with generator installation, to do the work up to code. Have a dealer or the professionals you plan to hire to install your generator evaluate your location and tell you what it'll take to install the system (and if you rent, have your landlord approve the installation).

Standby generators wired into your business' electric system require proper installation to prevent generator failure or overheating, and damage to your existing wiring and equipment. You'll also need a plumber to connect the gas or propane line, if applicable. Standby generators can be sensitive to both fuel pressure and volume, so high-quality connections are important.

• Look at location: The location of your existing electric service panel and gas line is important. The generator will sit outside but near your building, much like a central air conditioner, and for ease of installation, it's best if it can be positioned near the electric panel. The generator will need to be installed on a level surface - most commonly, a concrete pad but occasionally hard rubber. Some dealers cover "everything" in their installation charge, including pouring a concrete pad.

• Get an automatic transfer switch: To connect a standby generator to your existing electrical system, you'll need a separate device called an automatic transfer switch. The transfer switch is an essential a safety system that prevents your generator from feeding electricity back to the neighborhood power grid. When the power goes out, the generator will start up automatically, and after a few seconds to let it stabilize, the transfer switch will connect the generator to your office. When power comes on again, the switch will disconnect the generator and return your setup to normal. Do not attempt to install a transfer switch yourself. Installation of transfer switches may require local permits - but it always requires a professional electrician. The model of transfer switch will depend mainly on the size of your generator. In very high-priority situations such as hospitals, higher-end transfer switches can be worth the extra cost.

• Consider installing a dedicated electrical sub-panel: In addition to the generator and transfer switch, you may want to invest in a dedicated electrical sub-panel, as well. Only your essential equipment is connected to the sub-panel, which is connected to the generator. That way, when power fails, your critical devices will get the emergency power without the risk of overworking your generator or having to turn off or unplug other equipment. Setting up an electrical sub panel may be included in an installation charge, or may carry a separate fee.

Competent dealers of commercial generators can make a big difference in your overall satisfaction with your backup power system. Look for dealers who are knowledgeable and with a proven track record of dedication to generator sales and service. Large industrial or construction equipment dealers who happen to sell generators as a side business may offer a good price - but they won't have the expertise of a dealer who's more dedicated to selling and servicing commercial generators.

Maintain your generator

Consistently well-maintained generators can last a long time. When looking at dealers or licensed service technicians, ask what maintenance services they'll provide. At a minimum, a standby generator requires an annual checkup of oil levels, air flow, and other factors. Expect to change oil and spark plugs, check coolant, and perform regular engine maintenance on an annual basis. Because maintenance and service are so important, you'll most often want a generator dealer in your local area. A more distant dealership can sometimes connect you with licensed service technicians who are in your area, which can be okay. When researching dealers and technicians, ask:

• How many service technicians and trucks do you have?

• How long have you been in business?

• How many commercial generators similar to my model have you installed in the past year?

• Which brands do you work with most?

• How long have you sold/serviced my brand of generator?

Some dealers offer a service plan than includes yearly visits. Pricing for a generator service plan will vary according to the size and type of generator you select. For example, a large, liquid-cooled generator takes longer to service than other types of generators.

Find Generators on eBay

Find Generators on eBay

Once you know what type of generator you want:

You can also search eBay listing titles for specific words. For example, if you want to find a 15 kW generator, type "15 kW generator" (without quotation marks) into the Search box. Click "Search title and description" to expand your results. Visit eBay's Search Commands page for more tips on searching with keywords.

If you can't find exactly what you want, try shopping eBay Stores, tell the eBay Community what you want by creating a post on Want It Now, or save a search on My eBay and eBay will email you when a match becomes available.

Buy Generators With Confidence

Buy Generators With Confidence

Hundreds of generators listed on eBay in the Business & Industrial category will likely interest you. When trying to select the right generator, get to know exactly what you're buying, research the seller, and understand how eBay and PayPal protect you.

Know your purchase

Many sellers put a lot of time into creating their listings, making an effort to ensure they include all the information buyers need. Carefully read the details in listings for the generators you consider buying and carefully review available photos. Before placing a bid or buying an item, be sure to:

• Have all your questions answered. If you still have questions after reading the listing and reviewing the photos, contact the seller using the Ask seller a question link in the “Seller information” box in the top right corner of every generator listing. Also request additional photos if you want to see the generator from a particular angle that isn’t shown in the photos included in the listing. If you have more questions than you can address in email, get the seller’s phone number and give him/her a call. Some generator sellers even include their phone number so you can call them directly. Just remember that you need to actually bid and buy on eBay in order to be covered by eBay and PayPal protection programs (see "Buyer protection" below for more details).

• Get delivery details. Calculate and include delivery costs into your final price. For smaller items, look at the cost of shipping and insurance. For larger items, you may simply need to include the cost of driving across the city or state if the generator is close-by or it may mean working with a shipping company that can transport the generator from anywhere in the country. To learn more about shipping costs, ask the seller or visit the eBay Freight Resource Center.

• Complete your transaction on eBay. Always complete your transaction on eBay (with a bid, Buy It Now, or Best Offer). Transactions conducted outside of eBay are not covered by eBay and PayPal protection programs (see "Buyer protection" below for more details).

• Know your payment options. Never pay for your eBay item using instant cash wire transfer services such as Western Union or MoneyGram. These payment methods are unsafe when paying someone you do not know. Instead, pay with PayPal for amounts less than $2,000 (including deposits), a money order, or direct bank-to-bank fund transfer. You can also finance certain generator purchases through Equipment Financing for eBay, provided by Direct Capital Corporation.

• Track items with eBay Toolbar. Use the free eBay Toolbar to track items you bid on and watch. It includes Account Guard, a feature that indicates when you're visiting a verified eBay or PayPal website and warns you when you enter your eBay password into an unverified site, even if it looks like eBay or PayPal.

Know your seller

Just as important as researching your generator purchase is getting to know the seller. Take time to research the seller so that you can feel positive and secure about every transaction. Look for key things when evaluating a seller.

• Positive Feedback: What is the seller's Feedback rating? How many transactions have they completed? What percentage of positive responses do they have? What do buyers and sellers say in their Feedback? Did the seller receive praise?

• Sales history: Find out how long the seller has been a registered eBay user and look at the types of items a seller typically offers. If the seller’s Feedback seems low, take the time to look at the Feedback details; sometimes a seller's Feedback looks low until you realize that they’re a generator dealer and their Feedback count comes entirely from generator or heavy equipment sales.

• Terms and conditions: What are the terms and conditions of the sale? Are the terms agreeable to you? Sellers typically set terms and conditions, but you should make sure you agree with them. If not, find another seller/ generator or contact the seller to find out if he/she is open to your suggestions.

• Good communication: Once you’ve initiated communications with the seller, how is he/she communicating with you? Is the seller courteous and professional? Is the seller responsive? Once you bid on a big-ticket item, communicate with the seller through My Messages in My eBay. All legitimate Second Chance Offer messages will come through My Messages and not to your email address alone. Always contact the seller before accepting a Second Chance Offer, and never respond to any request to send money via Western Union or other instant cash transfer service.

Buyer protection

In the unlikely event a problem arises during your transaction, you can typically work it out with the seller. However, if you can’t, eBay and PayPal are there for you.

• Pay safely with PayPal: PayPal enables you to pay up to $2,000 without the seller ever seeing your bank account or credit card numbers. Also, PayPal protects buyers 100% against unauthorized payments from their accounts.

• eBay Security & Resolution Center: Visit the Security & Resolution Center to learn how to protect your account and use eBay's quick and efficient resolution tools.