Generator Q&A Session
One disclaimer: The numbers below are estimates. Consult the generator manual or a dealer for precise information on any particular model.

Q. How do you figure out how many watts you need your generator to handle?
A. Add the watt usage of the items you think you must have running simultaneously. Generally, that number should be 90 percent or less of the maximum wattage of the generator you use. That number is known as the generators running (or rated) watts and is usually listed along with the maximum number on the label. The amount of power being used at any one time is called the load. You should never run your generator at the maximum load for more than 30 minutes. For instance, my tiny unit is rated for a 2,250-watt load. It could simultaneously handle a refrigerator (800 watts), microwave (625), computer (400), five 60-watt light bulbs (300) and radio (100) -- but nothing more.

Q. Say an appliance does not have watts listed on its back?
A. If an item lists amperes (amps) instead of watts, multiply the amp number by the number of volts (the standard U.S. household three-prong outlet provides 120 volts) to come up with wattage. For example, if your fridge requires six amps of power and uses a 120-volt outlet, you will be taking a 720-watt chunk from capability of your generator.

Q. A hot plate uses how many watts?
A. Tiny heating elements chew up power as incongruously as 131-pound hot dog-eating champ Takeru "Tsunami" Kobayashi throws down Nathan\'s Famous on Coney Island on the Fourth of July (He gains 8 pounds in 12 minutes of eating franks at the contest ... take it from an expert, that is incredible). That big fridge? A mere 800 watts. A hand-held hair dryer? 1,500. A hot plate? Up to a whopping 2,500.

Q. What are start-up (surge) watts?
A. There are two types of loads: resistive and reactive. A resistive load is the same at start-up as it is afterward (i.e. light bulb, toaster). A reactive load is much higher at start-up than it is afterward. This is because items with reactive loads usually contain an electric motor (refrigerator, power drill). The start-up watts for these items generally run at about 2.5 times the running watts. Your generator must be able to handle that momentary high number and should have a start-up watts maximum on its label. I have to make sure that my refrigerator is the first item I attach to the generator, simply to handle the start-up watts that reach up toward my generator\'s full capacity. After the unit settles in to its 800-watt running level, I can add the other "resistive-power" items.

Q. I want to run my generator at night, but do not want to disturb my neighbors. Is that possible?
A. There are some extremely quiet (and expensive) generators. Honda has a 3,000-watt model that can run as quietly as 49 dBa (decibels adjusted). For comparison, a quiet office is rated at about 45 dBa, shouting is 80 and a chainsaw is 110. The loudest generators top out at about 90 dBa. Dealers I talked to were nearly unanimous in praising Honda for its quiet operation.

Q. How much time will a full tank on a generator give me?
A. Depends on the load you are asking it to power and the size of the gas tank, among other things. If you run a generator non-stop at its rated watts limit, though, plan on filling up every six to eight hours.

Q. It seems like every crack-handyman neighbor is installing direct connections between their generators and their home electrical system. Can I do this?
A. Even for our electrically skilled friends, I would recommend that only a licensed electrician install a manual transfer switch. The switch itself costs between $200 and $1,000, and then labor costs get added. A permit is required.

Q. I have taken my generator out of its box and have started it up. How long before I have to change the oil?
A. As is the case with many other gas-powered machines at home, the motor oil that the generator comes equipped with must be changed after the first few hours of operation. After that, it should be changed every 25-50 hours of operation.

Q. How often should I run my generator?
A. Every three months (or less), the generator\'s engine should be exercised by running it for a half-hour or so. Additionally, gasoline stabilizer should be added to the tank in the off-season to keep sludge from building up in the engine.

Q. Do I plug in my fridge and then start my generator?
A. No. Make sure that you do not plug anything into your generator until after you have started it, and unplug items before turning it off.

Q. What if I do not have the strength or patience for a recoil (lawnmower-style) starting generator?
A. There are electric-start models that use a key to start. They typically cost more.

Q. I can not spend that much money for a generator. Do I have any other options?
A. Try renting. Check the phone book for a household appliance rental store. Since you probably would be renting in the aftermath of a storm, you could be standing in a long line.

Q. How much should I pay for my generator?
A. Depending on power, brand and options, portable gas generators primarily range from $700 to $5,000.

Q.  What do I do to make sure I do not injure myself or others using my portable generator?
A.  Here are some basic tips:

• • Never plug a generator into one of your home outlets. It can send electricity all the way out to power lines that are being repaired, causing serious injury or death to a worker.
     
  • Make sure your generator is operating outside the home (that includes the garage) because carbon monoxide fumes are lethal.
     
  • Do not refuel while the generator is in use.
     
  • Be careful not to spill fuel onto a hot generator (use a funnel if possible).
     
  • Do not go near the generator with a flame.

  • Check them out with Consumer Reports.