Home Generators


Some customers prepare for the possibility of power outages by buying an electric generator as a standby system to keep lights and appliances running until service is restored. Since most outages in Roseville are less than an hour, a generator may be more than you need. A simple UPS (uninterruptible power source), which is a battery-backup system typically used for computers, may be sufficient.
During a prolonged outage, a generator may be able to save food in your refrigerator or freezer, let you keep your home office running, or power other essential equipment. But generators can be expensive and noisy. They can also pose serious safety hazards to you and to others, so please follow all safety instructions provided by the manufacturer.

Before purchasing a generator for emergency home use, consider these issues:

  • Check the noise output of the generator. Noisy generators may violate the City of Roseville's noise ordinance. Check the city's municipal code, “Title 9 Health and Safety,” section 9.2.4. Or call the city's Code Enforcement within the Building Division at (916) 774-5332.
  • Check for setback requirements. The generator should be five feet from the home or the fence. If the fence is a non-combustible wall, consult the generator manual; usually a three-foot setback is the minimum.
  • For units wired into your building, check with the City of Roseville's Building Department at (916) 774-5300 for permits. The Building Department will look at the wiring and setbacks to ensure the safety of you and your property.

The facts about generators

Generators take mechanical energy from a spinning shaft and turn it into electrical energy. For most home applications, the mechanical energy is supplied from an internal combustion engine.

Generators are available in many sizes, voltages, and fuel types. Sizing a generator for your application is a critical step and should be done in consultation with a reputable generator supplier or a licensed electrician.

Permanent generators are installed in homes and businesses to provide backup power during electrical outages. Generation of electrical power with a gas or diesel generator is more expensive than purchasing power from Roseville Electric, and should only be considered during power outages. In fact, home generation using gasoline, propane, or diesel is not permitted except for emergency use. If a homeowner wants to generate power on a continual basis, the photovoltaic (PV) program administered by Roseville Electric may be for you.

Important safety issues

Be sure to use your generator correctly. If you don't, you risk damaging your property and endangering your life and the lives of Roseville Electric line workers who may be working on power lines some distance from your home.

For safety reasons, Roseville Electric prefers that you plug appliances directly into the generator. You can also have a qualified, licensed electrician wire the generator into your home's electrical system. Either way, you should know that using a standby generator improperly can kill or severely injure you, your neighbors, and the people who are working to restore your power. Failure to use a standby generator properly may be a violation of the national, state or local electrical codes.

Only a qualified, licensed electrician should attempt to connect a standby generator to your main power system. Roseville Electric requires a double-throw switch with a mechanical or automatic interlock and a visible open between our service lines and the generator.

The following table of guidelines is provided for your safety and the safety of others.
IF YOU DO THIS THIS COULD HAPPEN HOW TO PREVENT IT
  • Attempt to connect generator directly to the electrical system of any building.
You can kill or injure a person repairing service lines. The electricity you generate could back feed through the building’s electrical system to the outside utility feed lines. Attempting to connect to the incoming utility service could result in electrocution. If Roseville Electric’s line crew is restoring electrical service while your generator is connected to the incoming utility service, you could start a fire or seriously damage your property. A qualified, licensed electrician must install a double-pole, double-throw transfer switch to connect the generator to a building’s electrical system. This is required by the National Electrical Code. Connection must meet local ordinances. A minimum of 10-gauge wiring must be used.

NOTE—only a licensed electrician can connect a generator to the main power supply.

  • Fail to ground the generator’s electrical system adequately.
The entire generator could become electrically charged and cause electrocution. Make sure that the unit is connected to an appropriate electrical ground in accordance with the National Electric Code. Follow instructions supplied with the generator.
  • Operate generator in rain, wet, or flooded conditions.
Water conducts electricity. If water comes in contact with electricity at the generator’s frame and other surfaces, it will cause an electrical shock to anyone touching them. Operate generator in a clean, dry, well-ventilated area. Make sure your hands are dry.
  • Use worn, damaged, undersized, or ungrounded extension cords.
Contact with worn or damaged extension cords could cause electrocution. Undersized extension cords could overheat wires or attached items, resulting in fire. Use of ungrounded cord sets could prevent operation of circuit breakers and result in electrical shock. Inspect extension cords before use and replace if necessary. Use proper size (wire gauge) cord set for application. Follow instructions supplied with your unit. Always use electrically grounded cord sets.
  • Attempt to fill the fuel tank while the engine is running.
Gasoline and gasoline vapors can become ignited by coming in contact with hot components such as the muffler, engine, exhaust gases or an electrical spark. Turn engine off and allow it to cool before adding fuel. Make sure there’s a fire extinguisher in the immediate area certified to handle gasoline or fuel fires.
  • Store fuel in makeshift containers.
Fuel could leak out causing a fire hazard. Fuel could be mistaken for another substance, creating a fire hazard, eye hazard, or possible poisoning. Purchase storage tanks intended for a specific use, such as a gasoline can for gasoline storage, or a propane tank for propane storage.
  • Fail to ventilate generator by operating in an enclosed area.
Obstructing ventilation causes overheating and possible ignition of the materials. You will produce toxic carbon monoxide exhaust fumes from the engine. Breathing exhaust fumes can cause serious injury or death. Operate generator in a clean, dry, well-ventilated area. Keep objects away from unit during operation. Do not operate unit in a confined area, such as garages, storage sheds, etc., which lack a steady exchange of air. Never operate unit in a location occupied by humans or animals. Keep children, pets, and others away from the generator.
  • Operate generator on dry grass, weeds, or near a building, fence, or other flammable materials.
Generators run hot, and are sources of ignition. Operation in such conditions could start a fire, burning down your house as well as your neighbors. Operate the generator at a safe distance from combustible materials. See your generator instruction manual for further information.
  • Tamper with factory-set engine speed settings.
Tampering with the engine speed adjustment could result in overheating of attachments and could cause a fire. Never attempt to “speed up” the engine to obtain higher performance. Both the output voltage and frequency will be thrown out of standard by this practice, endangering you and the attachments.

Connecting your house

If you improperly connect an emergency standby generator to your main electrical supply, it could “back feed” into your utility's power system and kill you, your neighbors, and electric utility crews working to restore power.

"Back feed" means that electric power is reintroduced to the utility's power lines through improper connection of the generator. This re-energizes lines that were thought to be de-energized. Roseville Electric crews work from maps to show where power is disconnected, but an improperly connected generator can re-energize lines that should be off, creating a safety hazard. Aside from the safety hazard, back feed can also cause serious damage to your electrical appliances and devices.

In addition, you should never touch a downed power line. You can't tell if the utility's power is off—and even if it is, a misconnected generator in the neighborhood could electrocute you.

Your electrician can install the proper switching equipment to prevent back feed and make sure the setup meets national, state, and local electrical codes. Your electrician can also ensure compatibility with Roseville Electric's power system.

Other hazards of running a standby generator

Besides back feeding, the generator itself has some hazards associated with it. Even if you are plugging appliances directly into the generator, you must still be careful of these dangers.

Standby generators are sized to provide power at a very specific, limited capacity. Do not exceed the rating capacity on the generator's nameplate. Overloading can cause serious damage to the generator and to your appliances. Home emergency standby generators usually run on gasoline, which must be handled properly. Be sure there is adequate ventilation in the area.

When using an extension cord, be sure it is of adequate size and has a three-prong, grounded plug. Make sure the cord is covered or otherwise protected from foot traffic.

An emergency generator has moving parts like any other engine, so be sure to keep children and pets away from it. Adults should also be careful around the machine.

When more than ten gallons of gasoline is on site, store the fuel in a listed metal flammable-storage locker with self-closing doors. Lesser quantities of flammable liquids should be stored in vapor-tight, approved containers apart from ignition or heat sources.

What size standby generator do you need?

Before operating a generator, list all of the appliances that are going to operate at the same time. Then determine the starting wattage requirements and the running wattage requirements. The starting load lasts only for a few seconds, but is very important when figuring your total wattage to be used. Your generator must be rated to handle the total wattage.

Wattage requirements vary with different brands of appliances. Be sure to check the nameplate on the appliances you plan to use. Always start your largest electric motor first, and then plug in other items one at a time.

Talk to your vendor or retailer about the size emergency standby generator that is appropriate for your needs. You should also talk to a licensed electrician to be sure that the appliances or equipment you have in mind can be run safely. Keep in mind that only a licensed vendor and electrician can be sure that your needs are met and the generator is installed safely.

Also remember that except for lights and electronics such as TVs and stereos, most household appliances have a starting current that is much higher than the running current. When sizing your generator, you must allow for the starting currents of air conditioners, fans, pumps, etc.

  • Basic—freezer, refrigerator, and one or two lamps. If your primary interest is keeping food from spoiling during a long outage, this should be enough. Refrigerators and freezers require fairly high currents so check the nameplate on your appliance (usually in the back, near the motor). Also, if you are not on city water and sewer, you may consider your well pump and septic system as basic appliances.
  • Heavy duty—air conditioner, furnace/air conditioner fan, and sump pump. All these items have large starting current requirements, often six or more times the running current. Air conditioners are particularly heavy energy users. Again, check the nameplate on your appliances.
  • Extras—TV, stereo, computer, or home security system. These items have relatively low wattage requirements compared to the appliances listed above, but they can be easily damaged if you overload your generator. Note that while computers don't require much wattage, most printers are heavy energy users.

Practical Tips

In addition to selecting and installing your generator safely, there are several important safety rules to follow when operating the generator.
Always read and follow the guidelines in your operator's manual.

  • Know how to shut the generator off quickly in case of emergency
  • Never modify a generator in any way
  • Never refuel a generator while it is running or hot
  • Periodically run the generator to assure it will start and run properly
  • Use adequately sized extension cords
  • Operate the generator in the open—never in a building or enclosure
  • Set the generator on a firm, level surface
  • Operate the generator in a dry location

If you are considering installing an emergency backup generator, contact generator equipment dealers. They can help you select a system that will safely provide temporary power when needed without creating additional problems or hazards.