Preventive Maintenance

Cleaning
• Cleaning is a major part of keeping a computer system healthy:
• Use a lint-free soft cloth (chamois) for cleaning the plastic outer-surfaces of the system
• Outer-surface cleaning can be accomplished with a simple soap-and water solution, followed by a clear water rinse
• Cleaning should be followed by the application of an anti-static spray or anti-static solution

Preventive Maintenance Procedures
Computer equipment is susceptible to failures caused by:
• Dust buildup
• Rough handling
• Extremes in temperature

Heat Buildup
• Check for other sources of heat buildup around the computer and its peripherals. These sources include the following:
• Direct sunlight from an outside window
• Locations of portable heaters in the winter
• Papers/books piled up around the equipment
• Computer furniture design and placement (creating a lack of free air space around the computer)

Protecting Monitors
The preventive maintenance associated with monitors consists of:
• Periodic cleaning, dusting, and good commonsense practices around the monitor.
• Aerosol sprays, solvents, and commercial cleaners should be avoided because they can damage the screen and cabinet.
• A simple cleaning solution is fine for cleaning the monitor
• Make sure that the monitor’s power chord is disconnected from any power source before washing
• The monitor’s screen should be dried with a soft cloth after rinsing

Caring for LCD Displays
• The screen should be cleaned periodically with a glass cleaner and a soft, lint-free cloth
• Spray the cleaner on the cloth and then wipe the screen
• Never spray the cleaner directly on the screen
• Avoid scratching the surface of the screen
• Take care to remove any liquid droplets from the screen because they can cause permanent staining
• After cleaning, allow 30 minutes for complete drying

Protecting Hard-Disk Drives
• Rough handling is responsible for more harddisk drive damage than any other factor.
• The drive should never be moved while you can still hear its disks spinning
• If a hard-disk drive is to be transported or shipped, make sure to pack it properly
• At no time should the hard drive’s housing, which protects the platters, be removed in open air.

Protecting Removable Media Drives
Removable cartridges or disks can be adversely affected by:
• Extremes in temperature
• Exposure to magnetic and electromagnetic fields
• Bending
• Airborne particles that can lead to information loss

Maintaining Removable Media Drives
Cleaning kits are available for:
• Floppy drives
• CD/DVD drives
• Tape drives

Protecting Input Devices
• An occasional dusting and cleaning should be all that’s required
• Input peripherals generally require very little preventive maintenance






Power-Line Protection
Typical power-supply variations fall into two categories:
􀁺 Transients—overvoltage conditions that can be classified as spikes (measured in nanoseconds) or as surges (measured in milliseconds)
􀁺 Sags—undervoltage conditions that include voltage sags and brownouts. A voltage sag typically lasts only a few milliseconds, whereas a brownout can last for a protracted period of time

Surge Suppressers
There are two factors to consider when choosing a surge suppresser:
• Clamping speed—how quickly the protective circuitry reacts to changes in the incoming power level and attempts to limit the change
• Clamping voltage—the designated voltage level that the device will attempt to maintain

Uninterruptible Power Supplies
• Uninterruptible Power Supplies (UPS) are battery-based systems that monitor the incoming power and kick-in when unacceptable variations occur in the power source
• Can be either a standby power system (offline) or an active power system (online)