Lenovo U300E manual Electrical safety

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Safety information

Electrical safety

Observe the following rules when working on electrical equipments.

Important:

Use only approved tools and test equipments. Some hand tools have handles covered with a soft material that does not insulate you when working with live electrical currents.

Many customers have rubber floor mats near their machines that contain small conductive fibers to decrease electrostatic discharges. Do not use such kind of mat to protect yourself from electrical shock.

•• Find the room emergency power-off (EPO) switch, disconnecting the switch or electrical outlet. If an electrical accident occurs, you can then operate the switch or unplug the power cord quickly.

•• Do not work alone under hazardous conditions or near the equipment that has hazardous voltages.

•• Disconnect all power before:

Performing a mechanical inspection

Working near power supplies

Removing or installing main units

•• Before you start to work on the machine, unplug the power cord. If you cannot unplug it, ask the customer to power-off the wall box that supplies power to the machine, and to lock the wall box in the off position.

•• If you need to work on a machine that has exposed electrical circuits, observe the following precautions:

Ensure that another person, familiar with the power-off controls, is near you.

Attention: Another person must be there to switch off the power, if necessary.

Use only one hand when working with powered-on electrical equipment; keep the other hand in your pocket or behind your back.

Attention: An electrical shock can occur only when there is a complete circuit. By observing the above rule, you may prevent a current from passing through your body.

When using testers, set the controls correctly and use the approved probe leads and accessories for that tester.

Stand on suitable rubber mats (obtained locally, if necessary) to insulate you from grounds such as metal floor strips and machine frames.

Observe the special safety precautions when you work with very high voltages; instructions for these precautions are in the safety sections of maintenance information. Be extremely careful when you measure the high voltages.

•• Regularly inspect and maintain your electrical hand tools for safe operational condition.

•• Do not use worn or broken tools and testers.

•• Never assume that power has been disconnected from a circuit. First, check it to make sure that it has been powered off.

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Contents Lenovo IdeaPad U300e First Edition Oct Copyright Lenovo 2011. All rights reserved Contents About this manual Safety information General safety Electrical safety Lenovo IdeaPad U300e Hardware Maintenance Manual Safety inspection guide Grounding requirements Safety notice Safety notices multilingual translationsLenovo IdeaPad U300e Hardware Maintenance Manual Safety information Lenovo IdeaPad U300e Hardware Maintenance Manual Safety information Lenovo IdeaPad U300e Hardware Maintenance Manual Safety information Laser compliance statement Safety information Strategy for replacing FRUs Important service informationImportant notice for replacing a system board Strategy for replacing a hard disk driveImportant information about replacing RoHS compliant FRUs General checkout What to do first Following are not covered under warrantyChecking the AC adapter Power system checkoutChecking operational charging Lenovo IdeaPad U300e Hardware Maintenance Manual Restoring the factory contents by using OneKey Recovery Related service informationPower-on password PasswordsSupervisor password Screen blank mode Power managementSleep standby mode Hibernation mode Lenovo IdeaPad U300e SpecificationsSpecifications Status indicators Status indicatorsHotkey Function key combinationsScrew notices FRU replacement noticesRemoving and replacing an FRU Removal steps of base cover Base coverLenovo IdeaPad U300e Hardware Maintenance Manual Removal steps of battery pack Battery packRemoval steps of hard disk drive Hard disk driveRemoval steps of Dimm DimmRemoval steps of PCI Express Mini Card for wireless LAN PCI Express Mini Card for wireless LANWhen installing Removal steps of fan assembly and heat sink assembly Fan assembly and Heat Sink assemblyLenovo IdeaPad U300e Important notices for handling the system board System boardRemoval steps of system board Lenovo IdeaPad U300e Hardware Maintenance Manual Removal steps of speakers and microphone Speakers and microphoneRemoval steps of the speakers and microphone Removal steps of LCD unit LCD unitWhen installing Removal steps of keyboard and keyboard bezel Keyboard and keyboard bezelM2 × 3 mm, flat-head, nylok-coated Black M2 × 5 mm, flat-head, nylok-coated Black Lenovo IdeaPad U300e Hardware Maintenance Manual Front view LocationsBottom and Left-side view Right-side viewParts list Overall No. FRU FRU no Parts list-OverallLenovo IdeaPad U300e Hardware Maintenance Manual Keyboard Parts list-KeyboardLenovo IdeaPad U300e Hardware Maintenance Manual Miscellaneous parts Parts list-Miscellaneous partsAC adapters Parts list-AC adaptersParts list-3-pin power cords Power cords145000525 145000553 UK 2PIN Parts list-2-pin power cordsLenovo IdeaPad U300e Lenovo IdeaPad U300e Hardware Maintenance Manual Trademarks