Cisco Chapter 2
Terms
- Blackout
-
complete loss of AC
Caused by:
- Blown fuse
- damaged transformer
- downed power line
-
Brownout
-
Reduced voltage level of AC
Occurs when:
- line voltage drops below 80%
- overloading
-
Noise
-
Interferance (unclean power)
Causes:
Generators
lighting
-
Spike
-
Short spike in voltage exceeds 100% normal
charactoristics:
Power comes back on
lighting strike
-
Power Surge
-
Dramatic increase in voltage above the normal flow of electrical current.
Can last a few nanoseconds or one billionith of a second
-
Power Protection Devices
-
Protect against power fluctuations
-
Surge Suppressor
-
Protects against surges or spikes.
Diverts extra voltage to ground
-
UPS
-
Uninterruptible Power supply
-
What don't you do with a power supply or CRT?
- use a static strap
-
Fire Extinguisher Classifications
A
-
Ordinary Combustible
- Paper
- Wood
- plastics
- cardboard
-
Fire Extinguisher Classifications
B
-
Flammable Liquids
- Gasoline
- Kerosene
- Organic solvents
-
Fire Extinguisher Classifications
C
-
Electrical Equipment
-
Fire Extinguisher Classifications
D
- Combustible Metals
- P-A-S-S
-
P - Pull the pin
A - Aim at the base of the fire not at the flames
S - Squeeze the lever
S - Sweep the nozzle from side to side
- How many volts must build up before it is felt?
- 3000v
-
How many volts to cause pain or make noise
- 10000v
-
How many volts will damage computer equipment?
- 30v
-
Uninterruptible power supply (UPS)
-
Provides electrical power to computer or device
-
What does a UPS do when power is lost
-
It is constantly recharging while the UPS is in use. Supplies quality power during brownouts and and blackouts.
- What does the UPS do with the OS?
- Allows UPS to safely shutdown the computer
- SPS
- Standby Power Supply
- Standby Power Supply (SPS)
-
helps protect against voltage drops below normal level.
Other things:
- The battery provides DC power to a power inverter, which converts it to AC power for the computer.
-
What makes the Standby Power Supply (SPS) not as reliable as the UPS
-
- Because of the time it takes to switch over to the battery.
- If the switching device fails, the battery will not be able to supply power to the computer.
- What is the hazardous materials of the computer called?
- Toxic Waste
- MSDS
-
Material Safety and data sheet
- What is a msds
-
summarizes information about material identification including:
hazardous ingredients that can affect personal health
fire hazards
first aid requirements
chemical reactivity and incompatibility
spill leak and disposa
- How do you determine if a material is classified hazardous?
- Contact Occupational Safety and Health Administration (OSHA)
- OSHA
-
Occupational Safety and Health Administration
-
What does OSHA require
- All hazardous materials must be accompanied by a MSDS when transferred to a new owner
- Chip3
-
Chemicals Hazard Information and Packaging
-
What does Chip3 require
-
chemical suppliers to safely package and transport dangerous chemicals and to include a data sheet with the product.
-
What does MSDS contain
-
- The name of the material
- The physical properties of the material
- Any hazardous ingredients contained in the material
- Reactivity data, such as fire and explosion data
- Procedures for spills or leaks
- Spec
- What are the reasons computers are discarded?
-
- Parts or components begin to fail more frequently as the device ages.
- The computer becomes obsolete for the application for which it was originally intended.
-
What rare earth metals to batteries contain?
-
Batteries from portable computer systems may contain:l
- lead
- cadmium
- lithium
- alkaline manganese
- mercury
- EPA
-
Envirnmental protection agency
- CRTs may contain 4lbs of what?
- lead
- what should you do when disposing of solvents and aerosols
-
contact local sanitation company
-
What are the 2 ESD tools?
-
- Anti static wrist strap
- Anti static mat
-
What does a static mat do?
-
protects computer equipment by preventing static electricity from accumulating on the hardware or technician.
-
What are 2 diagnostic tools used on computers?
-
- digital multimeter
- loopback adaptor
- What type of hand tools are used on computers?
- small hand tools
-
Disk managment tools
-
help detect and correct disk errors
prepare a disk for data storage
remove unwanted files
-
fdisk or disk management
- creates or deletes partitions of HD
- Format
- Prepares HD to store information
- Scandisk or CHKDSK
- checks integrity of files and folders by scanning surface of the disk for physical errors
- Defrag
-
Optimizes space on HD
-
Disk Cleanup
- Clears Space by searching for files that can be safely deleted
- Disk Managemnet
-
a system utility used to manage HDs and partitions
Includes:
- initializing disks
- creating partitions
- formatting partitions
- SFC
-
System file checker
-
SFC does what
- command line tool that scans the OS critical files and replaced the corrupted ones
-
Windows XP Boot Disk
-
Repairs corrupted files
windows system files
restore damaged or lost
reinstall the OS
Third party software is also avialable that does the same thing
-
Windows XP Security Center
-
Checks all security settings
Continously checks to make sure the firewall and antivirus are running
automatic updates
- Firewall
-
Protects against unauterized communications
-
Personal reference tools include
-
troubleshooting guides
manufacturer manuals
quick ref guides
repair journal
-
Internet reference tools
-
- Internet search engines
- News groups
- Manufacturer FAQs
- Online computer manuals
- Online forums and chat
- Technical websites
- What should you do before repairing equipment?
-
Make sure tools are in good condition
Clean
Repair
Replace
Anything that isn't in good working condition
- What does an antistatic strap do?
-
equalize the charge between you and the equipment
A conductor that connects your body to the equipment that you are working on.
- What type of clothing shouldn't you wear when working on computers?
-
silk
polyester
wool
-
when working at a workbench what should you do?
-
ground the workbench and the antistatic floor mat.
- hexagonal
- six sided
- Should you use magnatized tools on a compute?
- NO
- Why shouldn't you use pencils for dip switches etc?
- Pencil lead can act as a conductor and may damage computer components.
- What should you do before cleaning any device?
- Turn it off and unplug
-
what does dust do to computer components
-
acts as an insulator and traps heat
- What should you use to clean a computer case and monitor?
-
damp lint free cloth
one drop of dishwashing liquid with four ounces of water
-
Cleaning LCD Screens
-
Do not use ammoniated glass cleaners unless specifically designed for lcds
-
What should be used to clean component contacts
-
isopropl alchohol. Do not use rubbing alcohol.
Blow off with compressed air to remove any remnents of lint from q tip
-
What should you use to clean a mouse
-
glass cleaner and soft cloth
-
How do you clean a heatsink
-
compressed air
-
how do you clean a keyboard
-
hand held vacuum with brush attachment