power supply ppt

7/30/2019 Power Supply PPT

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Power SupplyPower supply - Internet URL

http://www.pcguide.com/ref/power/sup/index.htm
http://www.pcguide.com/ref/power/sup/index.htmhttp://www.pcguide.com/ref/power/sup/index.htm


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Purpose of the Power

Supply

Convert household power into a form thecomputer can use.

Provides power to every device in thecomputer.

The Power Supply converts AC (alternatingcurrent) which is external power to DC (direct

current) internal power that the computer canuse.

Link to AC/DC Voltage ConversionInformation

How Computer Work Video (Old Version)
http://www.pcguide.com/ref/power/sup/func.htmhttp://www.pcguide.com/ref/power/sup/func.htmhttp://www.pcguide.com/ref/power/sup/func.htmhttp://www.pcguide.com/ref/power/sup/func.htm


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Roles of the Power SupplyLink to the Role of the Power Supply

Stability provides sufficient power to PC.

Cooling - The power supply contains the main

fan that controls the flow of air through the PCcase.

Energy Efficiency - Newer PC power supplieswork with components to reduce the amount

of power they consume when idle. Expandability - The capacity of your power

supply is one factor that will determine yourability to add new drives to your system

A power supply is responsible for 28% of
http://www.pcguide.com/ref/power/sup/index.htmhttp://www.pcguide.com/ref/power/sup/index.htm


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Household Power &

Problems

Household Power the external power sourcethat comes into the wall.

Power Problems that may lead to powersupply problems.

Line Noise

Surges

Lightening strikes Brownouts

Blackouts

Link to Household Power and Problems
http://www.pcguide.com/ref/power/ext/index.htmhttp://www.pcguide.com/ref/power/ext/index.htm


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Line Noise

Line Noise - Line noise

consists of small

variations in the voltagelevel delivered to the

computer. Noise that

the power supply

cannot handle cancause it to malfunction

and pass the problem

on to your motherboard

or other internal devices


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Surges

This is a temporary increase of voltage

that can last just a few thousandths of a

second, but in this time the voltage canincrease from 110 to 1,000 volts or even

higher.

Voltage surges can disrupt or evendamage your computer equipment


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Lightening Strike

Enormous amount of electricity involved

in a storm, a strike near your PC--near

meaning within several miles--caninduce currents in metal objects.

Any wire that comes in from the outside

and attaches to your PC can become aconduit for a pulse of destructive energy

such as a telephone line or power cord.


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Brownout and Blackout

Brownout - when a brownout occurs, the

voltage drops from its normal level to a

lower voltage and then returns; in someways, it's like the opposite of a surge.

Blackout - A blackout, of course, is whenthe power totally fails.


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Basic ElectricityLink to Electrical Basics

This is an excellent site to link students

to the basics of electricity. This may be

to in depth for the IT Essentials Class. Idid not add this information to the

student worksheet. I added this page in

case instructors would like to teachadditional information about electricity

related to the power supply.
http://www.pcguide.com/ref/power/ext/basics.htmhttp://www.pcguide.com/ref/power/ext/basics.htm


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Parts of the Power Supply

Internal PowerParts of the Power Supply

Power supplies generate high voltages internallyand can be dangerous.

Unless you have been specifically trained to workinside power supplies, you should not open one.
http://www.pcguide.com/ref/power/sup/parts.htmhttp://www.pcguide.com/ref/power/sup/parts.htm


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Power Supply SpecsInput Voltages and Tolerances

Input Voltage Range acceptable range

of input 85v-135v AC or 170v-270v AC

Output Rating (Watts) output of powermeasured in watts

Link to

Calculating Watts
http://www.pcguide.com/ref/power/sup/spec_Elec.htmhttp://www.pcguide.com/ref/power/ext/basics_Power.htmhttp://www.pcguide.com/ref/power/ext/basics_Power.htmhttp://www.pcguide.com/ref/power/ext/basics_Power.htmhttp://www.pcguide.com/ref/power/ext/basics_Power.htmhttp://www.pcguide.com/ref/power/ext/basics_Power.htmhttp://www.pcguide.com/ref/power/sup/spec_Elec.htm


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Power Switch

Power switches to the power supply have

changed over time.

OlderPC/XT form factor computer was turnedon by a switch in the back of the computer.

AT form factor added a remote switch on the

front of the computer connected to the power

supply in the back.

ATX/NLX form factor uses an electric switch

connected to the motherboard that uses a

feature called Soft_Power to turn on the
http://www.pcguide.com/ref/power/sup/form_PCXT.htmhttp://www.pcguide.com/ref/power/sup/form_PCXT.htm


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Voltage Selector Switch

Normally dualvoltage selector tobe set at either110/220v.

110 Normalvoltage setting

220

For settingsout of the U.S.

If a 110v is set to220v damage can

occur.


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Motherboard Connector

Most important

connection.

Supplies power toother devices

through the

motherboard. Wires are made of

copper. ATX 20

pin

Older P8 & P9

Or P1 & P2


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Motherboard Connectors

Colors are used to depict the about of

voltage each wire may carry. (Most but

not all manufactures follow it.) The P8 and P9 must be inserted correctly or

the motherboard could be ruined. (Black to

Black your motherboards back, red to red

your motherboards dead.)

Power supply motherboard connectors are

based on the form factor of the motherboard.


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Motherboard Connector

Voltages

P8 P9

ATX

Style


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Drive Connectors

The power supply provides power to internalhard disk, floppy disk, CD/DVD and other drivesdirectly, through four-wire connectors that are

designed to attach to the rear of each drive The number of connectors that come with a

system may vary.

There is a specific smaller floppy drive

connector. Multiple larger four pin connectors may be used

on hard drives, CD-ROMS, and DVD.

A Y-Connector may add flexibility to drive

connectors but is not recommended.


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Drive connectors

Hard drive

CD-ROM

Floppy drive


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Power Supply Fan

Primary cooling source for the entirePC.

Power supply fans may be made ofdifferent components and movedifferent levels of air.

The fan is usually the first piece of thepower supply to fail because of dirt inthe air.

Most computers use additional auxiliary

fans to help cool the entire PC.


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Additional Hardware Help

Sysopt.com

tomshardware.com

cnet.com
http://sysopt.com/http://tomshardware.com/http://cnet.com/http://cnet.com/http://tomshardware.com/http://sysopt.com/

power supply ppt

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