It's a fact, power disturbances happen. People don't think about their electric supply until it is not available. It is taken for granted that when the switch is flipped the lights will come on.
Power disturbances can come in many forms, from a single blink of the lights to a full-blown outage. A power surge is a momentary increase in voltage whose effect may be too quick for the eye to see, but long enough to affect sensitive equipment. Surges are sometimes transient. Extreme, high-amplitude voltage surges are called spikes.
When electric power is generated, it is pretty close to perfect; however, it is very fragile and susceptible to many destructive forces which can affect it between the generation plant and your home or business. Electric power can also be subject to other forces that could distort it once it enters the service location.
Power disturbances are sudden changes in voltage (the force that brings electricity from the generation source to the service location). Some of the common types of disturbances result from animals and trees that come into contact with power lines; storms, snow, and ice; power tools and motors on various kinds of pumping, heating, and cooling equipment; and accidents involving utility poles and lines.
There are protective devices on the system to help protect the system's equipment from possible damage; however, that does not mean that it will protect the equipment in your home or business.
One of the protective devices on the system is called an OCR, or Oil Circuit Recloser. An OCR is similar to a circuit breaker; however, it is designed so that when a disturbance occurs on the system, rather than tripping off line, it will attempt to close in the system three times before it opens causing an outage. You may have noticed your lights flicker three times before the power stays on or goes off. This is an indication that the OCR is attempting to reset itself.
Protection for your sensitive electronic equipment is highly recommended. The circuit breakers at a service location are designed to protect the overall system by tripping offline when a short or other disturbance occurs. Circuit breakers are not sensitive enough to protect your electronics as the reaction time is simply not fast enough.
Today's electronic equipment is extremely sensitive to power fluctuations. In fact, many manufacturers build in minimal protection devices. Unfortunately, some high and low voltage situations can surpass the level of protection provided.
Surge suppressors can and do protect electronic equipment from high voltage situations. Surge suppressors come in a variety of makes and models and are readily available in most hardware stores. That's what they are designed to do. The amount of surge that will cause the suppressor to shut off power is printed on the suppressor. Appliances are plugged into the surge suppressors which in turn are plugged into grounded electrical outlets. Some surge suppressors feature connections for television and telephone lines to protect the equipment from surges when connected. Some surge suppressors come with protective equipment warranties, read the packaging before you buy. They do not protect equipment from any under-voltage situations.
Uninterruptible Power Supply (UPS) units are considered the ultimate protection and are normally used to protect computer systems or other sensitive electronic equipment. These devices use a battery charger to charge an internal battery; the computer is then powered by an inverter which draws its power from the battery. This protects the connected equipment, if sized correctly, from virtually all power problems, including sustained over– or under-voltage situations. When purchasing a UPS unit, you need to know what equipment you will be connecting to it, what the combined wattage is of the connected equipment, and how long you want the battery to last.
CVEA recommends purchasing UPS units with line conditioning features. The line conditioning feature helps to maintain a constant voltage going to the connected equipment.