CIS 1620-Chapter 2

Antistatic wrist strap

A strap that connects you to an antistatic pad to prevent static electricity from damaging computer components

Cleanliness

Clean hardware regularly to avoid problems caused by built-uo dust -use compressed air to clean delicate components -use a specialized vacuum to clean dust from other hardware -avoid blowing dust into other hardware or all over your office

Three-pronged Parts Retriever

A three-pronged parts retriever is used to grasp and retrieve small parts that have fallen into areas that are difficult to reach.

Standby Power Supply (SPS)

An offline device that switches over to provide power when an under voltage occurs. If the switch over is not fast enough, the computer loses power

Unplug the system before working on internal components

Do not rely on the power cord for an electrical ground.

Warning:

During certain conditions, such as an electrical storm or when the power supply is constantly going up or down, you might need to unplug the computer to protect it. Simply turn it off might still damage the components because some power remains supplied to the system. In the case of an electrical storm, keeping the system plugged in leaves it susceptible to power spikes

Risk Analysis

Identify risks associated with the change. For example, allocating additional funding to the project may strain another project's budget. Adding a new member to a team may negatively impact the team's effectiveness as training the new member will cause stress and consume time. Explain why the risks you identify are work taking, and present a plan for mitigating risks and avoiding problems.

Approval Process

If the change board approves your change request, then the change is proposed to the end user, usually a customer, for approval. Ensure that you receive written approval from all necessary parties to protect yourself and others from misunderstandings and their expensive and destructive effects Once all parties approve a change, all of the documents associated with a project must be updates to reflect the change, including the project plan, budget, allocated resource documentation, and any other projects the change affects.

Electrostatic Discharge (ESD)

The flow of electricity from one electrically charged object to another

Button batteries

These are considered hazardous waste because they contain mercuric oxide, lithium, silver oxide, or zinc-air. Return to manufacturer, recycle, or contact local authorities for disposal procedures

Nickel-Cadmium (NiCad) Batteries

These are considered hazardous waste; take these batteries to either a household hazardous waste site or a recycling center

Change Order Form

To request permission to make a change, you must submit a change order form to a change board. This is a document used only to request permission to make changes to a project. A change board is a predetermined group of people who have the power to accept or reject proposed project changes. It may include managers, project managers, or even the CEO.

Combination ractchet/ screwdriver

a combination ratchet is a ratcheting handle with interchangeable bits that provides multiple features in a single tool -bit ends can be replaced with Phillips and flat-head screwdrivers, hex sockets, and torx (star-shaped) bits -the ratcheting handle allows you to drive the screw without repositioning the driver Most computer components use Phillips head screw drivers

Surge suppressor

a device that protects systems from damage from a power surge by suppressing the over-voltage

Surge protector

a device that protects systems from over-voltages by switching the system off

Uninterruptible power supply (UPS)

a device that provides battery power to a computer in case of an under-voltage or power failure

Capacitor

a device that stores an electric charge

Change order form

a form that must be completed and submitted to a change board to request permissions to change a project's purpose, scope, schedule, budget, team, or other significant component

multimeter

a handheld device with a digital readout used to test electrical properties

Combination ratchet/screwdriver

a multi-tool with interchangeable bits

Backout Plan

a plan for returning affected systems and hardware to their original state if a new implementation fails

Change board

a predetermined group of people that must approve proposed changes to a project that is underway

Line Conditioner

modifies the power signal to remove noise and create a smooth alternating current (AC) signal

Change Management Facts

organizations document project plans and processes. if you need to make changes to a project after it is underway, you must go through a change management process

Surge

over voltage that lasts seconds

Material Safety Data Sheets (MSDS)

periodically review and update. An MSDS describes safe handling and disposal procedures for dangerous materials and can provide you with the knowledge to resolve an uncertain situation.

Surge protector

protects against over voltages by switching a device off before an over voltage can damage it -a power strip provides multiple power outlets from a single plug-in, but is not necessarily a surge protector -surge protectors can be destroyed by surges and lose their ability to protect -consider using a surge protector with an indicator light to show whether it is working correctly

Radio frequency interference (RFI)

signals caused by cordless phones, microwave ovens, and wireless devices that interfere with wireless networking

Static Electricity

the accumulation of a friction-caused electric charge on a non-grounded object. That static charge on the surface of a non-grounded object can jump when it contacts the surface of any grounded object. This electric discharge is known as electrostatic discharge (ESD). ESD can be very destructive to a computer.

Scope

the extent of a project, area, or subject; what is included and what is not

UPS

-designed to provide enough power to shut a system down safely during an extended power outage. Most are not intended as long-term power solutions -The UPS connects to the power source (usually a wall socket) the computer plugs into the UPS and the UPS is connected through a serial or USB port to the computer. Software on the computer uses this connection to monitor battery life and to detect when the regular power is lost. You can configure the software to shut the system down automatically when the battery charge reaches a certain level. You usually need to configure the following settings when working with UPS software: -Time to wait before sending a warning to clients -time to wait before beginning a shutdown -name of programs or commands to run during shutdown In addition to providing power when the power is lost, most UPS devices sound an alarm when the AC power is lost. This alarm continues until AC power is restored, although many UPS devices have a switch to mute the alarm.

Implement the following measures to defend components from ESD:

-keep the relative humidity in the room at an ideal range of 35%-70%, and temperature between 72-77 degrees. The key is to avoid dry air in the computer repair location to prevent ESD. -use antistatic mats under the PC and on the floor -Discharge yourself before touching any computer component -when touching anything inside the computer, wear an antistatic wrist strap that is attached to the metal PC chassis with an alligator clip -ground both yourself and the computer to the same ground. This provides a single path for the flow of electrical potential. -use static-resistant materials to handle computer components -never touch the metal connectors on a circuit board -keep the computer repair location free of materials that accumulate electric charges, such as plastic and styrofoam. -store sensitive components in static shielding bags, which are usually grey. Static-resistant bags are not nearly as effective. They are usually tinted blue or pink -if a wrist strap is unavailable, keep your body in constant contact with the metal frame when working inside the computer.

UPS

-size is measured by the volt-amp (VA) rating. The capacity of the UPS determines the number of devices and how long the devices can run when power is interrupted. -When purchasing a UPS, purchase one with enough battery power to power only critical devices such as the computer and a single monitor. --to reduce the amount of power required by the UPS, do not plug non-critical devices in to the UPS --laser printers require more power than most UPS systems are capable of providing. For this reason, you should not connect a laser printer to a UPS>. If you must provide power to a laser printer, get a dedicated UPS for that device

POST card

A POST card is an expansion board that you insert into an expansion slot. It is typically used to troubleshoot a computer system that doesn't start up correctly. The POST card displays output from the BIOS during the Power-On Self-Test (POST_

Power Supply Tester

A power supply tester is a custom multimeter used to test output from a Pc power supply. The power supply tester has multiple connectors to test the output for each connector type.

Cable Tester

A cable tester verifies that a network can carry a signal from one end to the other and that all wires within the connector are in the correct positions. Most testers have a single unit that tests both ends of the cable at once. Many testers come with a second unit that you can plug into one end of a long cable run to test the entire cable.

Peripheral device

A device that connects to a computer, such as a monitor or printer

Line conditioner

A device that modifier power signals to remove noise and create a smooth AC electrical signal

Material Safety Data Sheet (MSDS)

A document that contains safe handling and disposal processes for dangerous materials.

Loopback plug

A loopback plug is used to test network communications by redirecting a signal from the transmit port on a device to the receive port on the same device. Use the loopback plug to verify that a device can both send and receive signals.

Multimeter

A multimeter is a device that tests various electrical properties. For example, most multimeters can measure: -AC and DC voltage -Current (amps) -Resistance (ohms) -Capacitance -Frequency

IC insertion and extraction tool

A plastic and metal took used to add and remove integrated circuit chips

IC Insertion and Extraction Tool

An IC insertion and extraction tool is used to add or remove integrated circuit chips that are used on motherboards and some computer components. For example, on some motherboards, you can use the IC insertion and extraction tool to change the BIOS chip.

Antistatic Pad/Wrist Strap

An antistatic pad provides an insulated covering to prevent static electricity from moving between objects and damaging computer components. When working with computer components use a wrist strap connected to the antistatic pad and connect the pad to a ground.

Extension Magnet

An extension magnet is a small magnet on a collapsible rod. Use the extension magnet to retrieve screws that have fallen into a computer case or other area you cannot reach. As an alternative to a magnet, use an extension tool with retractable prongs.

Lifting

Be careful when lifting heavy objects. -bend your knees and keep your back straight, using your legs to lift objects -wear a back brace for added protection if your job requires frequent lifting -use carts and other tools when moving heavy objects for any significant distance -ask for help, if necessary, when lifting or moving heavier objects -follow the weight limitation guidelines defined by your employer.

Safe Device Use

Be safety-minded when using devices as well. Avoid the temptation to use mobile devices, such as tablets and cell phones, while walking and driving.

Threat of ESD

Begins when the fragile components (processor, hard drives, memory, motherboard, expansion cards) inside the computer are exposed. You can cause damage simply by placing a fingertip too close to a component inside an open computer case. ESD charges can travel through wires and into components, where the wires can explode or fuse together, causing the components to fail. ESD can cause immediate failure of components or could gradually degrade components, causing only intermittent problems. It takes very little ESD to damage a component. A discharge of as little as 10 volts can damage a component, but 3000 volts or more of ESD must occur before you can even feel it.

Blackout

Complete power failure

Thermal

Components such as the CPU heat sink and fan, the printing head of a dot matrix printer or components inside a laser printer can be hot. After turning off a computer or printer, allow components to cool sufficiently before servicing to prevent burns

Surge supressor

Conditions power so that over voltages don't reach devices

Cleaning Solutions and Solvents

Consult the MSDS, a licensed disposal organization, or local authorities for handling and authorized disposal procedures

CRT Monitor

Contact local authorities for recycling these. CRTs contain many toxic and caustic substances that are illegal to incinerate. Also, discharge before disposal (CRTs can contain high voltages)

Power Supply

Contact local authorities. Recycle, if possible. Discharge before disposal (contains high voltages.)

Scope

Define exactly what you wish to change, and if helpful, what you won't wish to change

Fire

Every room in which you work should be fire suppressed -have at least a Class C fire extinguisher available. A Class C fire extinguisher is made for electrical fires. -Make sure fire extinguishers and fire suppression methods (e.g. sprinklers) are properly implemented and maintained -promptly report any potentially hazardous situations -make the safety of others your top priority in responding to any incident. In the even of a hazardous situation, clear people from the area or remove the danger before attempting other actions such as preventing or repairing damage to components.

ESD and High Voltage

Exercise great care hen working with electricity. -Use ESD wrist straps to not only protect components, but to reduce the chance of accidental electrical shock. Properly ground yourself before working with components. -Do not use an ESD wrist strap when working with monitors, power supplies, laptop LCD panels, or other high-voltage components -Exercise caution when wearing jewelry, because it readily conducts electricity and could cause burns or even electrocution.

Heating, Ventilation, and Air Conditioning (HVAC)

For computer components, design HVAC systems with the following in mind: -keep temp between 70 and 74 degrees to prevent components from overheating -keep humidity 40%-70% to prevent electrostatic discharge (ESD) -make sure server rooms have separate ducting or HVAC systems from the rest of the building for better temp control -use positive pressure systems. positive pressure systems protect the air quality in the facility by causing air to be forced out through doors, windows, and other openings. Negative pressure systems draw air in, potentially bringing in airborne particles such as dust or smoke. Positive pressure systems are more energy effective. -in areas with heavy smoke or dust, add filters to air intake systems to filter out airborne particles

Troubleshooting Process Facts

Good troubleshooting is a process that combines knowledge, experience, and intuition.

Known Good Spares

Known good spares are a set of components that you know are in proper functioning order. If you suspect a problem in a component, swap it with the known good component. If the problem is not resolved, troubleshoot other components. Examples of using this strategy are: -changing the cable connecting a computer to the network -connecting a different monitor to a computer -replacing an expansion care

Magnetic Fields

Located close to a computer can cause undesired effects or even data loss. -Hard drives use magnetic charges to store data. While hard disks are shielded and protected from all but the strongest magnets, getting a magnet too close to these components could erase data. -Speakers, motors, and generators contain magnets, (keep sensitive components away from these devices.) -Solid state storage devices (such as RAM or flash drives) are not affected by magnetic fields

Physical

Make sure the room and the building are properly set up to ensure your safety. -keep work areas and floors clear of clutter to help prevent accidents -do not route cables across the floor in pathways. This can lead to tripping accidents and could also result in worn cables -provide adequate ventilation in any enclosure to remove toxic fumes -protect yourself from airborne particles by using an air filter mask -wear safety goggles -replace worn or frayed power cords

PC Maintenance Facts

One of the most important things you can do to keep a computer system running is create a proper environment

Spike

Over voltage that last milliseconds

Peripherals

Peripherals can present a safety hazard to you. -do not use a regular multimeter or other electrical testing equipment to measure charge inside a monitor -never clean the monitor's glass with a liquid solvent while the monitor is powered on -some studies suggest that laser printers emit tiny particles which could be dangerous when inhaled. As a precaution, do not locate laser printers immediately next to desks, and keep the area ventilated. -avoid handling leaky batteries. The leaking electrolytes can be harmful if they get into your eyes -Never look into the end of a fiber optic networking cable. Laser light can damage your eyes

Power

Power hazards can cause electrical shock and burns. -before handling a system component, make sure that it is powered off and that the main power cord is unplugged from the wall socket -ensure that the grounding pin on a PC power plug is intact -unplug the system before working on internal components. Newer power supplies constantly pull power from the socket -Be aware that the power supply can retain an electrical charge, even when not plugged in. Replace faulty power supplies instead of trying to repair them. -Avoid opening the power supply which houses a capacitor (stores a large charge of electricity)

Backout plan

Present a plan for returning affected systems to their original state if your proposed change to a hardware or software implementation fails

Plan

Provide a plan for implementing the change. This plan may include extending the project schedule, requesting additional resources, requesting additional funding, and any other impacts to the project

Purpose

Provide an explanation about why you wish to make this change to the project

Change order forms generally require the following:

Purpose Scope Plan Risk Analysis Backout Plan

Nickel Metal Hydride (NiMH) Batteries

Recycle these; NiMH batteries are considered a non-hazardous waste in most US states, with the exception of California

Lithium and Lithium Ion Batteries

Recycle these; lithium batteries are considered a non-hazardous waste

PC System

Recycle, give it away, or resell it; a typical PC contains $5 to $25 worth of precious metals. Remember to clean the hard drive before disposing of the machine

Alkaline Batteries

Recycle, if possible, otherwise dispose of alkaline batteries as your local laws require. For example, in some states, you can throw them in the regular trash. In California, it is illegal to throw them in the common trash. They are considered hazardous waste and are supposed to go with the household hazardous waste collection for special recycling

Inkjet Printer Cartridges

Recycle; you can return the cartridges to the manufacturer for recycling or recycle them yourself

Laser Printer Toner Cartridges

Return to the manufacturer for recycling (to clean up spills, use a toner vacuum or a scoop and a damp cloth; never use a regular vacuum.)

Sag

Under voltage that lasts milliseconds

Brownout

Under voltage that lasts seconds (lights dim)

Electromagnetic interference (EMI)

a signal caused by motors, heavy machinery, and fluorescent lights that interferes with wired networking signals

Interference

a signal that corrupts or destroys regular signals. Interference affects signals used by two devices to communicate on a network. Two types of interference are Electromagnetic Interference (EMI) and Radio Frequency Interference (RFI)

Extension magnet

a small magnet on a collapsible rod used to retrieve parts that fall into a computer case or another area that hands cannot reach

three-pronged parts retriever

a small tool used to grasp and retrieve small parts that fall into places difficult to reach with hands

loopback plug

a small tool used to test network communications

power supply tester

a special multimeter used to test output from the PC power supply

Cable tester

a tool that verifies that network signals can travel throughout a network

Cathode Ray Tube (CRT)

a vacuum tube used to display images that is commonly used in computer monitors

POST card

an expansion board used to troubleshoot computer system startup

Antistatic pad

an insulated covering that prevents static electricity from moving between objects and damaging computer components

Standby power supply (SPS)

an offline device that provides power when an under-voltage occurs

Uninterruptible Power Supply (UPS)

an online device that is constantly providing battery power to the computer and being recharged by the wall outlet There are two types of UPS systems: -an offline UPS constantly powers the computer from the battery -an offline UPS powers the computer from the wall power. When the power fails, a switch inside the UPS switches to power the computer from the battery. This is the most common form of UPS.

Surge

an over-voltage that last seconds

Spike

an over-voltage that lasts milliseconds

Sag

an under-voltage that lasts milliseconds

Brownout

an under-voltage that lasts seconds

Capacitor

be sure to discharge capacitors or turn the equipment over to qualified personnel for servicing. Similarly, exercise caution when working with the DC converter in a laptop display.

Blackout

complete power failure

Radio Frequency Interference (RFI)

interference on the radio channel used by wireless networking devices -RFI Can be caused by wireless devices using the same channel, cordless phones, or microwave ovens -wireless networks that use the 2.4 GHz frequency range (801.11b and 802.11g) are susceptible to RFI -You can reduce RFI by using a wireless networking standard that operated in the 5.75 GHz range or using a different channel for wireless devices

Electromagnetic Interference (EMI)

interference that affects wired networking signals -EMI is caused by motors, heavy machinery, and fluorescent lights -Use shielded twisted pair cable to protect signals sent on Ethernet twisted pair cabling. If necessary, use fiber optic cables to eliminate the effects of interference.

Change Management

the process of regulating changes to a project once it is underway

Heating, Ventilation, and air conditioning (HVAC)

the system installed within buildings to control temperature by supplying heat and air conditioning