Preventive Maintenance 3
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Transcript of Preventive Maintenance 3
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Domingo M. Caya Jr.
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There are many aspects to system care and
maintenancethat affectthe system as a
whole, or every component in the system, as
opposed to being specificto a particularcomponent. These factors are discussed in
this section.
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In the last few decades we all have become
much moretuned into our external
environment and how it affects us. Well, it
affects your PC as well. We're much moreimportantthan PCs of course, but as it
happens, many of thethings that make
humans sick or uncomfortable,have a similar
impact on computers. This section takes alook atthese issues.
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The general rule of thumb for room
temperature is that PCs likethe
temperatures that (average, normal :^) )
people like. Generally speaking, goodoperating temperature for a PC is about 60
to 75 degrees Fahrenheit (15 to 24 or so
Celsius). Cooler than this is of course, better
than warmer.
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Operating a PC in a hot room that is over 80
degrees Fahrenheitcan make itvery difficult
to cool. Remember that some businesses
havethermostats on a timer that will makeair conditioning shut off at night; in this
situation you might wantto make sure a PC
is not left running overnight, or that a
special computer room is designated withindependentcontrols.
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Most PC hardwarecan tolerate being at much
lower temperatures (or moderatelyhigher
temperatures) when they are not running. If
you aretransporting equipment or storing it,thetemperatureconcerns are much less than
if theequipment is actually in use. However,
if youhaveequipmentthathas been exposed
to very low temperatures and is thenimmediately turned on, you risk permanently
damaging theequipment.
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If youtake a PC that is at freezing
temperature and plug it in, it will warm up
veryquickly, much morequickly than it
would if you left it on a tableto warm up inits own time. In somecases, youcan raise
thetemperature of equipment from 0
degrees to 150 in only a matter of minutes.
Thermal stress is a leading cause ofpremature failure of electronics components.
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Even more dangerous than this is the
possibility of condensation
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It is quite possible for this to happen with
electronicequipment as well. This does not
cause any problem as long as you givethe
condensation enoughtimeto evaporate. Ifyour hard disk platters are "moist" when you
spin them up, you risk destroying the drive.
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Much as thecase is withtemperature,
computers prefer moderatehumidity as
opposed to either extreme. PCs are not as
sensitiveto humidity issues as they aretotemperature, butthey are still affected by
it.
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Obviously,computers and moisture don't mix
well; you need to keep your computer dry.
That means keeping it away from places or
things thatcan get it wet. This includes theobvious: don't put a PC in the bathroom or
kitchen, for example. It also includes
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Humidity leads to corrosion and possible
condensation risk, whichcan damage
equipment. It also makes cooling the PC
more difficult. Conversely, air that is too drycan cause problems in two different ways.
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First, it increases the amount of static
electricity that is in the room, increasing the
chances of a discharge. Second, itcan cause
faster wearout of somecomponents that dryout over time. This includes sometypes of
capacitors, as well as rubber rollers on laser
printers.
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Finally,humidity can exacerbate problems
related to dramaticclimatechanges. Going
from a cold environmentto a warm onecan
lead to condensation, which is why you mustwait for the PC to warm up beforeturning it
on. Obviously, if the warm environment is
also a humidone,thechances of
condensation are increased
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Computers operate best when they areused
in a clean environment, and when they are
cleaned regularly. Most offices and homes
areclean enoughthat a PC requires nospecial treatment other than regular cleaning
as part of routine preventive maintenance.
Industrial environments however can be
murder on PCs.
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PCs that are going to beused in dirty
circumstances should be protected or
cleaned more often. Oneeasy preventive
measure is to use an air cleaner in the roomwherethe PC is located. There are also
special cases and enclosures for PC hardware
designed for industrial environments to
safeguard against damage dueto dirt. Theaverage PC owner only has to remember to
clean their equipment occasionally and no
problems will generally result.
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Many problems,especially unreliable storage
devices, are related to cigarette smoke
accumulating on read/writeheads and
media.
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All electronic devices give off
electromagneticemissions. This is radiation
that is a byproduct of electrical or magnetic
activity. Unfortunately,theemissions fromone devicecan interfere with other devices,
causing potential problems.
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Interferencecan lead to data loss, picture
quality degradation on monitors, and other
problems with your PC, or problems withother devices such as television sets and
radios. These are generally categorized as
electromagnetic interference or EMI
problems.
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Two different issue
EMIemissions by the PC,
EMIemissions received by the PC.
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PCs generally do notcausevery much
interference with other devices;they are
required by the Federal Communications
Commission (FCC) to becertified as Class Bdevices.
This certification is used to show thatthe PC
conforms to standards that limitthe amount
of EMIthat a PC can produce.
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The only catchto this is that youhaveto
keep thecover on the PC. This is one reason
why thecover is always made from metal.
(Keeping thecover on is also an importantpart of ensuring proper ventilation).
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PCs can be affected by electromagnetic
interference from other devices, in two
major ways
directeffects through proximity with otherdevices
electrical interference over the power lines.
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EMI if youthink it is affecting your PCs:
Physical Isolation: Devices thatemit
electromagnetic radiation should be kept areasonable distance from your PC, peripherals
and media. This includes television sets, radios,
lights, kitchen appliances, and stereo speakers
(the ones designed for use with PCs are generally
shielded and are much less of an issue).
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Use Dedicated Circuits: Many office
buildings especially,have separate power
circuits that are intended for use by PCs.
Keeping your PC on a circuitthat is separatefrom thecircuit running your refrigerator
and air conditioning unit means thatthere
will be much less interference passing to the
computer from the other devices (and this
will also improvethequality of the power
being sentto your machine in general).
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Power Conditioning: Theuse of a line
conditioner or uninterruptible power supply
can filter out interferencecaused by otherdevices that share a line with your PC.
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keeping your system cool is very important. A
cool system runs more reliably and lasts
longer than onethat runs hot. Overheating of
the internal components can lead to dataloss or even damageto your equipment. In
recent years, as processors in particular have
gotten faster and hotter,the subject of
cooling has become more importantthan
ever.
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Internal Air Flow
The "first line of defense" in cooling the overall
system is the fan that is used to provide overall
air flow within the system case. This is normallythe fan located within the power supply atthe
back of thecase; some newer machines,
especially full-tower cases,employ morethan
one fan,to provide morecooling.
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It's importantto realizethatthe fan (or fans)
used in thecase and/or power supply work
by establishing a flow of air throughthe
case.
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There aretwo basic designs used.
In a standard baby AT stylecase,the power
supply fan blows outthe back of the power
supply, and in doing so it draws air throughtherest of thecase and thereby,cools the
components insidethecase.
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In the newer ATX style of case and power supply,
the power supply fan is on theinside of thecase
and blows inwards, pushing air throughoutthe
case and drawing it in throughthe back of the
power supply,exactly the opposite.
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In bothcases, for thecooling to work
properly,the flow of air must not be
interrupted. The better, and stronger,the
flow of air,the morecooling it willaccomplish. If the flow is notestablished
correctly, at best only some of the
components will becooled.
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General System Care
Factors
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