How to Buy A Good Standby Generator - Diesel Generator

When buying a standby generator, you have to consider some important factors as a new in the field of electrical equipment. What questions or factors should you consider? See the following answers.

1. What kind of fuel will your standby generator use?

Whole house generators can run on natural gas, propane or diesel. While natural gas is one of the best fuel sources, you should not discount a propane or diesel-powered generator. It all depends on your needs and whether natural gas is supplied to your home. If natural gas is present, confirm the pressure is compatible with the generator requirements. Some standby generators require more pressure and this means your utility company installing a larger gas meter for your home.

Alternatively, you can choose liquid propane gas as the generator fuel source. You can store the fuel in a large tank and use it when needed, with no worries of liquid propane gas spoiling. The tank does not have to disrupt the curb appeal of your home, as you can place it underground to keep it out of sight.

Lastly, there are diesel generators, which are quite durable. Most diesel generators have an internal fuel tank, or an option to purchase a sub-base fuel tank (a tank that sits under the diesel generator). Diesel fuel can spoil, so some extra maintenance is required by adding a fuel treatment to diesel at least once each year.

2. What size generator is the best for your needs? The size of a whole house generator is dependent on the number of electrical appliances you want to power and the size of your home. It is best to get a professional to advise you on the size. If you buy one that is too small, you will not be able to run your HVAC and all appliances and gadgets.

3. Where will the generator be located?  The generator set should be located where it’s readily accessible for maintenance and repair, and high enough to keep rising water from reaching the generator. For outdoor and rooftop installations, comply with code requirements for minimum distance from combustible walls and building openings. For indoor installations, adhere to requirements for fuel supply, ventilation, exhaust ducting, and proximity to combustible materials. Typically the generator should be located as close as possible to the transfer switch and fuel supply.

4. If outdoors, which enclosure type?  A follow-up question:  Is there a local noise ordinance? Some areas require the sound level of the standby system to be within a specific decibel rating at the nearest property line. If a specific sound requirement exists, the target sound level will determine the type of generator enclosure. Many residential or light commercial generators come standard with a sound attenuated enclosure while industrial grade generators may offer several enclosure types ranging from a standard weather enclosure to a custom package to meet strict requirements.

5. What is the voltage requirement? Common low voltages for the U.S. are: 120/240 volts single phase, 120/208 volts three phase, 120/240 volts three phase, and 277/480 volts three phase. If you are unsure, your electrician can provide this information.

6. Which type of transfer switch?  Transfer switches for emergency standby systems are usually the automatically controlled type. Manual transfer switches can be supplied for certain systems if preferred, although this lack of automation usually doesn’t come with much of a cost savings. The size of the transfer switch (amperage rating) and installation location should be determined by your electrician and may depend on the earlier question of “entire building or just emergency loads?” If the system is sized to carry the whole building, the transfer switch may need to be service entrance rated which incorporates a utility disconnect within the transfer switch cabinet. For commercial/industrial applications, several other transfer switch features are available such as bypass isolation, closed transition, and programmed transition.

7. Any specific accessory requirements? Accessory options will vary depending on the generator type. Residential or light commercial systems typically offer an optional remote annunciator panel which provides generator status and can be located in a preferred area indoors. Cold weather kits and remote monitoring are also available for many residential/commercial systems. For industrial systems, the number of available options is much greater, including an expanded list of communication options, enclosure lighting, alternator strip heaters, load centers, etc.