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• Follow electrical safety guidelines to prevent electrical fires, injuries, and fatalities
• Some printer parts, such as power supplies, contain high voltage
• Check the printer manual for the location of high-voltage components
• Some components retain a high voltage even after the printer is turned off
• Electrical devices have certain power requirements
• Exchanging AC adapters with a different type of laptop or device may cause damage to both the AC adapter and the laptop
• Electric equipment must be grounded
• If a fault causes metal parts of the equipment to become live with electrical current, the ground will provide a path of least resistance for the current to flow harmlessly away
• Typically computer products connect to ground via the power plug
• Large equipment such as server racks that house network devices must also be grounded
• Electrostatic discharge (ESD) can occur when there is a buildup of an electric charge (static electricity) that exists on a surface which comes into contact with another, differently charged surface
• ESD can cause damage to computer equipment if not discharged properly
• ESD buildup

  1. At least 3,000 volts of static electricity must build up before a person can feel ESD

  2. Static electricity can build up on you as you walk across a carpeted floor. When you touch another person, you both receive a shock. If the discharge causes pain or makes a noise, the charge was probably above 10,000 volts

  3. Less than 30 volts of static electricity can damage a computer component
• Static buildup can be discharged by

  Touching a grounded object prior to touching any electronic equipment
• Self-grounding


  Touching a grounded object prior to touching any electronic equipment to discharge static buildup
• ESD can cause permanent damage to electrical components
• Recommendations to prevent ESD damage

  • Keep all components in antistatic bags until you are ready to install them
  • Use grounded mats on workbenches
  • Use grounded floor mats in work areas
  • Use antistatic wrist straps when working inside computers
• Desktop computer case

  Houses the internal components such as the power supply, motherboard, central processing unit (CPU), memory, disk drives, and assorted adapter cards
• Case

  The framework to support, protect, and cool the internal components
• Form factor


  The physical design and look of a desktop computer
• Desktop computer form factors

  • Horizontal case
  • Full-Size Tower
  • Compact Tower
  • All-in-one
• Other desktop computer form factors

  • Super tower
  • Full tower
  • Mid tower
  • Mini tower
  • Cube case
• Computer components


  Tend to generate a lot of heat
• Computer cases

  1. Contain fans that move air through the case

  2. Absorb heat from the components

  3. Exit the case
• Computer cases

  Protect against static electricity damage
• Computer’s internal components

  Grounded via attachment to the case
• Computer case


  Also referred to as the computer chassis, cabinet, tower, housing, or simply box