From the Gulf Coast to the Eastern Seaboard coastline, experts remind us of the annual threats from the hurricanes. The headlines scream, “Prepare for the storm.” We scrutinized numerous checklists on important steps to protect your home, family, and business in the event of a natural disaster.
Mother Nature can really throw some challenges at us. Too much of any weather condition is enough to test the power grid wherever you are. Too much heat, too much cold, too much rain, too much wind are just some of the problems that nature has thrown at the power grids that serve our communities. What are you going to do when the power goes off and stays off for days? That is when we activate whatever we have setup for backup power.
We uncovered an area of preparation that is often neglected or mishandled: backup power. The major box stores like Lowe’s and The Home Depot sell thousands of portable generators to the panic-driven public. Home power units and power units for small businesses are a really good idea, if properly sized and installed. Call your local licensed electrical contractor today. Ask your electrical contractor for an estimate to design and install your backup power system.
For many consumers, bringing home a portable power generator may be as risky as letting your children play with loaded firearms. Fuel, exhaust gases, and connections top the list of danger areas. Often, the buyer is uninformed about their real power requirements and the capabilities of their backup power system.
An average home (or small business office) may use more than a hundred electrical appliances and devices to provide convenience, comfort and security. Therefore, it is essential that we install a backup home generator to prepare for power outages. A residential generator has major advantages over a portable generator, with features like set-automatic start, permanent fixture, more power, cleaner fuel (natural gas or propane), low running costs and all-weather operation. Standby power systems start automatically within seconds after a home’s electricity goes out and ensure a continuous electrical supply. A transfer switch immediately senses when power is interrupted and transfers power generation to a generator. It also senses when power is restored and transfers the load back to the utility source and signals the generator to shut down. The power generator is installed outdoors and linked directly to the home’s permanent fuel supply.
Jim Irvin, president of Riverside Electric, in South Florida, relayed some of the specifics that are part of a typical installation for standby power systems. Irvin also explained how the system could work and what happens when the power goes out. Clearly, the electrical contractor is a valuable resource as you plan for predictable power in an unpredictable world.
A residential standby generating system typically has three basic elements: a generator, a transfer switch and a service-entrance breaker.
1. Generator—Produces electricity for essential or selected systems like cooling, heating, refrigeration, security and lighting. Your backup needs, simple or more extensive, determine the size and output of the unit.
2. Transfer switch—Immediately senses when power is interrupted and transfers power generation responsibility to the generator. Senses when power is restored and transfers the load back to the utility source and signals the generator to cool off and shut down.
3. Service entrance breaker—Provides protection to your transfer switch, internal breakers and circuits and generator due to electrical strikes and power surges.
Note: Electrical connections must be made and fuel systems installed by qualified and licensed personnel. Improper installations present hazards, which can result in personal injury or property damage.
How the system works
1. Transfer switch monitors voltage coming from utility
2. Transfer switch senses when utility power fails or drops below an acceptable level (brown out), and sends a signal to start the generator
3. Transfer switch automatically disconnects the utility power from the electrical circuits in your home, and reconnects them to the generator
4. Generator continues to supply electrical power to your home until utility power is restored
5. Transfer switch senses when the utility power is restored, automatically disconnects the generator from your home circuits, and reconnects the utility power
6. The standby generating system automatically re-sets itself for the next power outage
What happens when the power goes out
Power outage occurs
When utility power voltage falls to less than 85 percent of nominal or fails entirely, the standby power system will automatically go through a start sequence and connect to a home. The transfer panel control constantly monitors the power quality from both the utility source and the generator set. When the transfer panel control senses unacceptable utility power, the control waits for 3 seconds and then sends a signal to start the generator set engine. If the utility power returns before 3 seconds has passed, the generator set engine will not be signaled to start. When the start signal is received, the engine starts and reaches the proper operating speed, and alternating current (AC) power is available at the generator set. The transfer panel control senses this, waits for 3 seconds and will then transfer generator set power to the home through the transfer panel contractors. This sequence of operations will usually occur in less than 10 seconds from the time the power outage occurred to the time when generator set power is connected.
Utility power returns
When utility power comes back on and returns to your home, the transfer panel control senses this and will watch for acceptable voltage. After checking for acceptable utility voltage for five minutes, the transfer panel control will signal the transfer panel contractors to re-transfer the load back to the utility source and disconnect the generator set source. At this point, the generator set is "off-line" and will be operated automatically another five minutes to properly cool down. After the cool down cycle, the generator set will be turned automatically off and reset to standby mode
Routine operation and maintenance
A common concern for homeowners is how to maintain their standby generator once it is installed. Not to worry. Maintaining a generator is similar to maintaining an automobile, and maintenance is essential for top performance and long life. Just like a car, you will have an owner’s manual for your generator unit with very specific directions and maintenance intervals in grid form. It will tell you how to maintain your generator and allow you to record things like running hours and maintenance performed. You will find that changing the oil, checking the battery/connections, changing an air or oil filter, and visually inspecting your unit’s components are typical maintenance requirements. Warranty work, however, must be performed by an authorized dealer or certified technician.
Small business applications
Recent news stories about the horrific heat wave have given the public ample notice of just how vulnerable the power grids have become. Outages, rolling blackouts, or brownouts can have a devastating impact on your operations. Many small businesses are essential to operation of a community. Power is a must for them to continue operations when nature strikes. Check with your local electrical contractor to develop your own “what if” plan when the power goes off. Think of the plan as a life preserver.
The cost of being powerless is hard to measure. Each business must make that evaluation individually. Building owners may also consider these systems for multi-tenant sites. We could not find a table to measure the cost to your business if the unthinkable happens. A stitch in time saves nine.
BISBEE is with Communication Planning Corp., a telecom and datacom design/build firm. He provides a free monthly summary of industry news on www.wireville.com.