Comptia A Ch.4 Flashcards
antistatic wrist strap
A strap that connects a tech to a computer that equalizes the voltage potential between the two to prevent ESD
auto-switching
A type of power supply that monitors the incoming voltage from the wall outlet and automatically switches itself accordingly. Auto-switching power supplies accept voltages from 100 to 240VAC at 50 to 60Hz. They are popular in laptops and great for international travel.
amp
short for ampere, a measurement of current
Alternating Current (AC)
describes an electrical current in which the electrons flow in two, opposite directions. Type of electrical power from a wall outlet
AC circuit tester
device used to check a wall outlet’s wiring
ACPI (Advanced Configuration and Power Interface)
Technology that allows the motherboard and operating system to control the power needs and operation modes of various devices
Berg
type of power connector that extends from the computer’s power supply to a floppy drive
blackout
total loss of AC power
brownout
loss of AC power due to electrical circuits being overloaded
EMI (electromagnetic interface)
Electric noise generated by electrical devices. Also called EMR (electromagnetic radiation)
ESD (electrostatic discharge)
Occurs when stored up static electricity is discharged in an instantaneous surge of voltage. Cumulative effects weaken or destroy electronic components.
Energy absorption/dissipation
surge protector feature which describes that the greater number of joules that can be dissipated, the more effective and durable a surge protector is
grounding
Occurs when the motherboard or adapter is not installed properly and has a trace touching the computer’s frame.
dual-rail power supply
A term used to describe two +12 volt lines available in a power supply.
DC (direct current)
type of power a computer needs to operate
Clamping Voltage
voltage level at which a surge protector begins to protect a computer
Clamping Speed
time that elapses from an overvoltage condition to when surge protection begins
continuity
An electrical resistance measurement to see if a wire is good or broken
current
term that describes how many electrons are going through a circuit
capacitor
an electronic component that can hold a charge
I/O Shield
part that allows for optimum air flow and grounding for the motherboard ports
Line Conditioners
Device that protects a computer from overvoltage and undervoltage conditions as well as adverse noise conditions. Also known as power conditioner
Li-ion Battery
A lithium battery, which is very light and can hold a charge for a long period of time. cell phones, cameras, etc.
MOV (metal oxide varistor)
electronic component built into some surge protectors to absorb overvoltage spikes or surges
Molex
type of power connector that extends from the computer’s power supply to various devices
Modem Isolator (phone line isolator)
surge protector for modem, protecting against power fluctuations in phone line - also called phone line isolator
Overvoltage
condition when AC voltage is over the rated amount of voltage
ohms
measurement of electrical resistance
resistance
a measure in ohms of how much opposition is applied to an electrical circuit
RFI (radio frequency interference)
A specific type of EMI noise that occurs in the radio frequency range. Often results from operation of nearby electrical appliances or devices.
Preventative Maintenance
something that is done to prolong the life of a device
Phone Line Isolator (modem isolator)
Surge protector for the modem, protecting against power fluctuations in a phone line - also called modem isolator.
Power Supply Tester
tool used to check DC voltages sourced from the power supply
Power Good Signal
signal sent to motherboard from the power supply during POST that signifies power is acceptable
Power
measurement expressed in watts that represents how much work is being done
pin 1
A designated pin on every cable and connector that must be mated when attaching the two. Usually designated by stenciled or etched number, color stripe, etc.
standoff
A plastic connector on the bottom side of a motherboard.
scribe
plastic tool that helps with prying plastics parts or covers off laptop and mobile devices
Standby Power (SPS - Standby Power Supply)
Power that is always provided, even when a computer is powered off - is why you have to unplug computer when working inside.
Surge Protector
Device that helps protect power supplies from overvoltage conditions. Also called surge strip or surge suppressor.
sag
momentary undervoltage condition that occurs when the wall outlet AC voltage drops
spike
overvoltage condition of short duration and intensity - 1 to 2 nanoseconds
surge
overvoltage condition like a spike but with longer duration - 3 or more nanoseconds
Wake on Ring
A BIOS and adapter feature that allows a computer to come out of sleep mode when the telephone rings, so can accept fax, e-mail, etc.
Wake on LAN
A BIOS and adapter feature that allows a network administrator to remotely control power to a workstation, and allows a computer to come out of the sleep mode.
watts
electrical measure in which computer power supplies are rated - a measure of how much work is being done. Determined by multiplying volts by amps.
volts
power supply’s output is measured in volts - also used to describe voltage from a wall outlet
voltage
measure of the pressure pushing electrons through a circuit - measured in volts
UPS (Uninterruptible Power Supply)
device that provides power for a limited time to a computer or device during a power outage
UL 1449 VPR (Underwriters Laboratories voltage protection rating)
voltage protection rating standard developed by UL to measure max amount of voltage surge protector will let through to attached devices.
undervoltage
condition that occurs when AC power drops below 100 volts, which may cause computer’s power supply to draw too much current and overload
Type A-B-C Fire Extinguisher
fire extinguisher that can be used on Type A, Type B, or Type C fires
Type C Fire Extinguisher
fire extinguisher that can be used only on electrical fires
TVS Rating (transient voltage suppressing)
measure of surge protector’s ability to guard against overvoltage conditions - the lower the TVS, the better
