PC PRO 6.0 2.5 PC Maintenance

Blackout

Complete power failure

Spike

Overvoltage that lasts milliseconds

To prevent electrostatic discharge (ESD), keep humidity between:

40 and 70 percent

Interference

A signal that corrupts or destroys regular signals.

Line Conditioner

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

Sag

Undervoltage that lasts milliseconds

Clean removable media devices using

-Compressed air to blow dust and debris off of CD-ROM and DVD disc surfaces, out of drive bays, and off of drive heads. -Soft, dry lint-free cloths to wipe smudges off of CD-ROM and DVD disc media surfaces.

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

Be aware of the following tips for maintaining your computer:

-When receiving a new computer or component that has been shipped, let it sit for at least six hours (24 hours if it arrives in outside freezing conditions) before applying power. The rapid change in temperature can cause damage to components or can result in condensation within the computer. -Perform regular backups. Backups protect your data if a hard disk fails. -You can use covers and cases to protect some equipment from dust and liquid spills. Be sure to remove covers before use and replace after use. -Keep cables organized. Route cables to prevent them from being kinked or stepped on. For best results, use cable ties to bind and organize cables. -Verify that your system's cooling fans are blowing air through the system case in the correct directions. A fan blowing in the wrong direction can negate the airflow through the case and cause the system to overheat.

To prevent components from overheating, keep temperatures between:

70 and 74 degrees

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.

In areas with heavy smoke or dust:

Add filters to air intake systems to filter out airborne particulates.

Standby Power Supply (SPS)

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

Negative pressure systems

Draw air in, potentially bringing in airborne particles such as dust or smoke. Positive pressure systems are more energy effective.

Dust buildup inside a computer acts as an insulator for internal components, trapping heat and preventing adequate cooling of components. Use:

Compressed air to blow dust off. A non-static vacuum to remove dust. A natural bristle paintbrush to wipe components off.

Radio Frequency Interference (RFI)

Interference on the radio channel used by wireless networking devices. -Can be caused by nearby 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 operates in the 5.75 GHz range or using a different channel for wireless devices.

Electromagnetic Interference (EMI)

Interference that affects wired networking signals. 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.

Common computer cleaning supplies include:

Lint-free cloth Compressed air or an air compressor Small anti-static vacuum Denatured or isopropyl alcohol

Surge

Overvoltage that lasts seconds

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.

Positive pressure systems

Protect the air quality in the facility by causing air to be forced out through doors, windows, and other openings.

Surge Protector

Protects against overvoltages by switching a device off before an overvoltage 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.

Cleaning Tips:

Regular cleaning gives you the chance to inspect all components. Look for worn or failed components. On electrical components, dark areas might indicate a burned-out component. Prior to cleaning computer components, power down and unplug components and let them sit for at least 30 minutes to cool. Use caution with liquid-based cleansers. Use small amounts and always apply cleaning solutions to cloths and cleaning instruments, never directly to component surfaces.

A UPS is 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.

Brownout

Undervoltage that lasts seconds (lights dim)

To clean electrical connectors (such as those on expansion cards)

Use a small amount of denatured alcohol on a cotton swab

uninterruptible power supply (UPS)

an online device that is constantly providing battery power to the computer and being recharged by the wall outlet.

For a mouse with a roller ball

clean the ball and the roller contacts on a regular basis.

In addition to providing power when the power is lost, most UPS systems also

condition the line and remove power spikes and sags.

Surge suppressor

conditions power so that overvoltages don't reach devices.

Online UPS

constantly powers the computer from the battery.

Make sure server rooms have separate

ducting or HVAC systems from the rest of the building for better temperature control.

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.

To clean LCD screens use:

lint-free dry cloth or a small amount of isopropyl alcohol (do not use window cleaner, ammonium-based cleaners, paper towels). You can also use special monitor-cleaning solutions or pre-packaged wipes with monitor-safe solution.

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.

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.

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 turning 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.

To clean a Printer

use a damp or dry cloth. -On inkjet printers, use the printer's cleaning function to clean the print heads. -For laser printers, use an anti-static vacuum to remove excess toner. (A regular vacuum will build up an electrostatic charge from the toner.)

To clean keyboards:

use a vacuum or compressed air. For keys that stick, use a lint-free cloth and/or cleaning swabs, lightly dampened, to gently wipe each key.

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.