Buying a Generator – Considerations

Now that you have decided to purchase a generator, there are several considerations you must keep in mind when choosing which unit to buy, where to install it and how to install it. This guide will help you select a generator using a step by step method. Choosing the right machine is not difficult if you take the time to analyze your requirements carefully. Power World is here to help, if you get confused or have a question, ask us.

PORTABLE OR STATIONARY?

Most homeowners first think of portable generators rather then stationary generators. If you want to haul a generator outside or put one outside in a shed and plug in cords when there is a power outage, it can be done. You will not necessarily save any money doing it but if you have a use for the portable generator for non-emergency times then it might be an alternative. It has been our experience that it is more economical and less hassle to purchase a stationary system and power the whole house or business. Not only do you get more power for the dollar but your family and/or employees don't have to do anything to have emergency power. Do you want your wife, children or employees hauling out equipment and plugging things in and starting up the system, switching the transfer switch and having to refuel? At some point all of this becomes ridiculous and costs you more in staff time and potential liability then its worth

STAND-BY OR PRIME?

The first determination you will need to make is whether you will require stand-by or prime power. Simply stated, prime power is required when you have no other source of power or you are using the system as you prime means of power. Any generator that is used everyday or on a fixed schedule to provide power is considered a prime power generator. Another word for prime is "continuous". If you need a prime power generator, use the generators prime or continuous rating as a a guide.
A standby set is a backup to normal utility power. Standby units are used only when your utility power is not available and will not be used frequently. Many stand by generators run at 3600 RPM and are not designed for constant daily use. Another word for standby is "emergency". If you need a standby power generator, use the generators standby or emergency rating as a a guide.

GENERATOR PHASES

Generator sets produce either single or three phase power. You should use the type of power your panel provides. Residences and small business generally use single phase. Three-phase power is used for medium to large businesses especially where power is used for motor starting and running. Three phase generators are set up to produce 120/208 or 277/480 volts. Single-phase sets are 120 or 120/240. Use the low voltage to run domestic appliances and the high voltage for your motors, heaters, stoves and dryers. Your service panel is either single phase or three phase, you don't need a three phase generator if your panel is only single phase. Check with your electrician before you begin your search.

GENERATOR AMPERAGE

Your service panel is a good place to start. Go and look at your service panel and see what the amperage is. If the panel is 100 Amps that tells you that your won't need more then 100 amps of power. As the panel gets bigger so will your generator needs. It is possible to install a generator to power only a small portion of your service panel, if you install appropriate sub-panels to sort out what will and will not be powered.

FUEL: GAS OR DIESEL?

We recommend diesels due to their longevity and lower operating costs. Today's modern diesels are quiet and normally require much less maintenance than comparably sized gas (natural gas or propane) units. Fuel costs per kW produced with diesels is normally thirty to fifty percent less than gas units.
1800 rpm water cooled diesel units operate on average 12,000 to 30,000 hours before major maintenance is required.
1800 rpm water cooled gas units normally operate 6,000 to 10,000 hours because they are built on a lighter duty gasoline engine block. Gas units burn hotter (higher BTU of the fuel) so you will see generally see somewhat shorter lives than the diesel units
3600 rpm air-cooled gas units are normally replaced ¨C not overhauled at 500 to 1500 hours. These are "stand-by" generators, not intended to be run long hours or very often.

OPERATING SPEED

Electric equipment is designed to use power with a fixed frequency: 60 Hertz (Hz) in the United States and Canada, 50 Hertz in Europe and Australia. The frequency output of a generator depends on a fixed engine speed. To produce 60 Hz electricity, most engines operate at 1800 or 3600 RPM. Each has its advantages and drawbacks. 1800 RPM, four pole sets are the most common and least expensive in large generators. They offer the best balance of noise, efficiency, cost and engine life. 3600 RPM, two pole sets are smaller and lightweight, best suited for portable, light-duty applications. 3600 RPM sets are considered "Standby Generators" and can never be considered for prime power use.
In simple terms it's like operating your car at 90 mph, versus 45mph ¨C at 45mph your car will last longer, is quieter, less maintenance and longer life. Most 3600 rpm units are twin cylinder air cooled lawn mower engines, while the water cooled 1800 rpm units are comparable to those found in forklift and tractor engines. The bottom line is the 1800 rpm water cooled units will last longer, offer less maintenance problems and be more fuel efficient. In addition, 1800 RPM generators are designed to be rebuilt, 3600 RPM units are designed to replaced and are much lower in cost (most of the time). Some 3600 RPM stationary units and most RV and commercial power units can be rebuilt at least one or more times but this process is not inexpensive.

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Diesel Generator,Diesel Generator Set manufacturer and suppliers - Power World Machinery Equipment Co.,Ltd was founded in1998. It's a department specialized in diesel generators export business.