Power and Place Determination

 To select an engine-driven generator, you will need to determine the power (kilowatt) requirments which must be met under operating conditions. 

Undersizing the generator can be avoided by considering all of the loads that will be connected to the generator, and by determining the starting requirements (motor start) of electric motor-operated devices.

 be sure the generator you select is large enough to handle your present requirements and anticipated needs.

To determine the right size generator, add up the total watts of all lights, appliances, tools, or other equipment to be connected to the generator. Check the nameplates to determine wattage. If wattage is not show, but amps and volts are given, the following simplified formula may be used:

Amps x Volts = Watts

To determine kilowatts (kW, use the formula:

1000 Watts = 1 kW

For best result, the measurement must be done by a professional technician.

 

Generator Placement

Choosing a location for your new standby generator is usually straightforward, but there are factors you must consider. A good location is one that allows the generator to operate efficiently and safely without endangering the lives of people living around. Always install standby generators outdoors on stable ground that does not flood. The exhaust gases produced by a generator contain deadly carbon monoxide, and that is yet another consideration for location.

 

Consult your local building code authority for necessary requirements and permits. They have the final say in all electrical and plumbing installations, and local ordinances may vary from standard codes and will often supersede the manufacturer’s recommendations. Experienced electricians and plumbers know how to work with local building departments to resolve conflicts between installation instructions and local building codes.

 

Minimize costs by placing the generator as close to the existing electrical service entrance as possible without getting too close.

 

Some general guidelines include placing your generator where prevailing winds will blow the exhaust away from the home/working place.Never locate the generator under an overhang, in a breezeway, or in recesses blocked by trees, shrubs or other vegetation. Avoid areas subject to snow drifts and protect the generator from pets, animals, people, and traffic.


Standard required clearances include three feet from any wall, five feet from any house opening, three feet from flammable materials. Never locate the generator anyplace that might allow exhaust gases to accumulate, under a roof of any kind, or inside any kind of building.

Generator Pads

After you’ve selected a location, have it approved by your local code authority. There’s nothing worse than purchasing materials and installing them, only to have your code inspector fail your installation because it didn’t meet local codes for placement. It wastes time and money.

 

Some localities require a concrete pad for the generator to sit on, others allow generators to sit directly on a bed of gravel or pea gravel. Most manufacturers supply their generators in an enclosure that includes a suitable base for the generator―provided the underlying surface is level.

 

A bed made from compacted sand with pea gravel on top makes a good pad. Remove the sod and dirt to make a rectangular shaped hole as large as required and six inches deep. Add a three-inch layer of damp sand and compact it. Make a 2-by-4 frame from cedar or pressure treated lumber to help enclose the gravel and keep it on the pad, and out of your grass. Level the frame with a spirit level, fill it with pea gravel, and you’re ready to set the generator on it.

 

Even when local codes require a concrete pad, it is still a good idea to build a base of compacted sand and set a frame on top of it. Level the frame and fill it with concrete. Once it hardens and cures, it’s ready for the generator.