Dell OptiPlex NX1 User's Guide - Page 22

Computer systems are sensitive to variations in voltage supplied by the AC power source. Overvoltage, undervoltage, and transients (or spikes) can erase data from memory or even cause components to fail. To protect against such problems, power cables should always be properly grounded, you should use a power protection device, and you should place the system on a circuit that does not contain any heavy electrical equipment. Your network administrator should verify your power source and network cables; however, you should ensure that your system is connected to a dedicated power circuit and that it is not sharing a circuit with any of the following: Kitchen appliances Copier machines Air conditioners Vacuum cleaners Space heaters Power tools Teletype machines Adding machines Any other motorized equipment Another threat to a system's supply of power is surges or blackouts caused by electrical storms. Whenever possible, turn off the computer and any peripherals and unplug them from their power sources during thunderstorms. If a blackout occurseven a temporary oneturn off the system immediately and disconnect it from its power source. Leaving the system on may cause problems when the power is restored; all other appliances left on in the area can create large voltage spikes that could damage the system. Various levels of power protection are available for your system. Surge protectors prevent voltage spikes, such as those caused during electrical storms, from entering a system through the AC power source. These devices are available in a variety of types and usually provide a level of protection commensurate with the cost of the device. Surge protectors, however, do not offer protection against brownouts, which occur when the voltage drops more than 20 percent below the normal AC line voltage level. 2-6 Dell OptiPlex NX1 Net PC Systems User's Guide