What is a surge?
A “surge” is a boost in electrical charge in a power line. This can be caused by lightning, but it is more commonly caused by high-power electrical devices such as air conditioners and refrigerators which require a lot of energy for starting and stopping compressors and motors. Some surges can also be caused by faulty wiring. Telephone and cable lines can also conduct high voltage and need surge suppression as well.
A power surge is one form of electrical power disturbance. There are four main types of power disturbances:
- Voltage dips (also called "sags" or "brownouts")
- Electromagnetic interference
- Radio frequency interference
- Power surges (also referred to as "voltage surges" or "transient voltages")
Power surges are generally considered to be the most destructive of the four types of electrical power disturbances. Power surges are spikes in voltage.
A spike in voltage can be harmful to appliances and electrical devices in your home. An increase in voltage above an appliance's normal operating voltage can cause an arc of electrical current within the appliance. The heat generated in the arc causes damage to the electronic circuit boards and other electrical components.
There are several sources of power surges.
- Electric utility company during power grid switching.
- Lightning, the most powerful form of power surge.
- Large appliances; air conditioners and refrigerator motors turning on and off.
Power surges can enter a home through several paths. Lightning can take the path of the cable TV, satellite dish cable, incoming telephone lines, or through the incoming electrical service line.
AC power protection is often overlooked when deciding a surge protection strategy. When providing protection, users are keen to apply surge protection devices, or SPDs, to process signal lines, transmitters, file severs and other important equipment as the source of surges is more obvious. However, a common source of surges is the AC power supply. It is important to note that any cable entering an electronic device is also a easy path for lightning current to enter and cause untold damage; the power supply is no exception.
