Electrical Generator

An electrical generator is a piece of equipment utilized as an alternate power supply backup to the utility's normal power supply servicing a customer's premises. The need of a generator as a power supply backup to the utility's electrical service to a building is a convenience for most residential applications but can be a life safety concern for hospitals and other medical office buildings throughout the country.

For instance, there are certain tasks in a hospital that are not allowed by local and national code requirements to have their service disconnected so as to maintain the safety and well being of the general public. These tasks include the functionality of an operating room, the energization of the facility's emergency egress lighting distribution system (that allows occupants to safely leave the building upon loss of the utility's normal power supply), the energization of air conditioning systems that maintain pressure between various classes of occupancies (to prevent the spread of infection diseases), the energization of vacuum and air pressure systems (to maintain various functions needed in procedural areas) as well as a certain number of general purpose receptacles in patient room areas in case of an immediate procedure being required.

An electrical generator may also be required as a power supply backup to utility's normal power supply for any commercial institution (even though there is no life safety concerns). The need for a generator may be deemed essential by a company's ruling board as a result of lost revenue to the company. Especially in this age of reliance on personnel computers, loss of the utility's power supply means that employees can no longer work and a company does not want to be paying employees for time that they cannot work. Additionally, loss of the utility's power supply may also mean that a company's product cannot be produced and if product cannot be produced, it cannot be sold. So, if a utility company is deemed to be unreliable a commercial institution may elect to have an electrical generator installed to prevent loss of revenue.

Private residences may also want to have an electrical generator installed upon loss of their utility power supply. There are several utility companies that have difficulty maintaining quality of service to residential areas when a storm hits their grid. This can be attributed to power lines running through trees and breaking upon the falling of limbs in high wind situations. It is becoming more and more prominent for residential areas to loose their utility power supply with the coming of inclement weather. Another issue with utility reliability may be the lack of maintenance to power lines by the utility companies. No matter what the case, after a while, a private resident may wish to have an electrical generator as a power supply backup to their local utility as a matter of convenience. In the summer time it may be nice to have electricity to run the air conditioner or in the winter time to run the heater; additionally, it may be nice to have electricity to run the refrigerator and freezer to prevent food from spoiling.

Now when an electrical generator is installed there are certain approvals that need to be acquired from the local utility and considerations that need to be addressed to maintain the safety of utility personnel. It is not just a matter of taking the leads of a generator and attaching it to the bus of your panel. There needs to be full isolation between the utility's power supply and the generator's power supply backup. This is a requirement of OSHA to insure safety to both utility maintenance personnel as well as private citizens. One simple method of ascertaining this electrical isolation is to utilize a transfer switch. A transfer switch will safely transfer electricity from one power supply to another without having either of the sources contact each other. In this way a utility power line will not become energized by the starting of an electrical generator feeding onto the utility's power line. This could be a grave occurance to utility personnel working on a power line trying to get utility power back on line for its coustomer.

This transfer switch can be an automatic transfer switch (that will automatically start the generator and transfer load to it) or a manual transfer switch (that will require a manual start of the generator and subsequent manual transfer to it). As one might expect, the automatic transfer switch is more expensive than a manual transfer switch so an automatic transfer switch may only be deemed necessary for hospitals and other commercial institutions where power is required by various local and national codes to be brought on line within a certain amount of time. One reason for this in a commercial building is that there are areas in a building that do not receive the light of day; therefore, having the power come on after loss of the utility's normal power supply is essential to the safety and well being of the building's occupants. Under this circumstance, it is not only worthwhile but also mandatory to have an automatic transfer switch. On the occasion that you are sitting at home watching a game on television and the power goes out, it would not be too big of a sacrifice to go outside and manually start the generator and transfer the electrical loads of your home onto it.

Since a generator does take a certain amount of time to start, there will always be an interruption of service to electrical loads during this interim starting time. For loads like a refrigerator or an air conditioner this will not have a detrimental affect; however, for a computer if you receive even the slightest "glitch" in your electrical power supply, you will loose all data that was not saved in a timely manner. Once again, this may not be detrimental to your personnel computer at home but, to the servers and computers of a business establishment, this could mean loss of valuable data which also could mean loss of revenue. Under these types of situations an unterruptible power supply (UPS) may be appropriate to install in series with your computer equipment to prevent loss of data. This UPS contains batteries that will allow you ride through any utility power outage for the interim period that is required to get the generator started.

So you see, having an electrical generator could be very advantageous to have as a power supply backup upon loss of your utility's normal power supply for commercial, institutional and residential occupancies.

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