3.Check the power cord for:

a.A third-wire ground connector in good condition. Use a meter to measure third-wire ground continuity for 0.1 ohm or less between the external ground pin and frame ground.

b.The power cord should be the appropriate type as specified in the parts listings.

c.Insulation must not be frayed or worn.

4.Remove the cover.

5.Check for any obvious alterations. Use good judgment as to the safety of any alterations.

6.Check inside the unit for any obvious unsafe conditions, such as metal filings, contamination, water or other liquids, or signs of fire or smoke damage.

7.Check for worn, frayed, or pinched cables.

8.Check that the power-supply cover fasteners (screws or rivets) have not been removed or tampered with.

Handling electrostatic discharge-sensitive devices

Any computer part containing transistors or integrated circuits (ICs) should be considered sensitive to electrostatic discharge (ESD). ESD damage can occur when there is a difference in charge between objects. Protect against ESD damage by equalizing the charge so that the machine, the part, the work mat, and the person handling the part are all at the same charge.

Notes:

1.Use product-specific ESD procedures when they exceed the requirements noted here.

2.Make sure that the ESD protective devices you use have been certified (ISO 9000) as fully effective.

When handling ESD-sensitive parts:

Keep the parts in protective packages until they are inserted into the product.

Avoid contact with other people while handling the part.

Wear a grounded wrist strap against your skin to eliminate static on your body.

Prevent the part from touching your clothing. Most clothing is insulative and retains a charge even when you are wearing a wrist strap.

Use the black side of a grounded work mat to provide a static-free work surface. The mat is especially useful when handling ESD-sensitive devices.

Select a grounding system, such as those listed below, to provide protection that meets the specific service requirement.

Note: The use of a grounding system is desirable but not required to protect against ESD damage.

Attach the ESD ground clip to any frame ground, ground braid, or green-wire ground.

Use an ESD common ground or reference point when working on a double-insulated or battery-operated system. You can use coax or connector-outside shells on these systems.

Use the round ground-prong of the ac plug on ac-operated computers.

Grounding requirements

Electrical grounding of the computer is required for operator safety and correct system function. Proper grounding of the electrical outlet can be verified by a certified electrician.

Safety notices (multi-lingual translations)

The caution and danger safety notices in this section are provided in the following languages:

6ThinkStation Hardware Maintenance Manual

Page 12
Image 12
Lenovo 4223, 4228, 4229 manual Handling electrostatic discharge-sensitive devices, Grounding requirements

4229, 4223, 4228 specifications

Lenovo has long been recognized for its commitment to producing high-quality computing solutions, and the ThinkPad line is no exception. Among its various models, the Lenovo ThinkPad series 4228, 4223, and 4229 stand out for their robust features and reliable performance, making them ideal choices for business and professional use.

The Lenovo ThinkPad 4228 series is engineered with a focus on durability and performance. One of its key features is the powerful Intel Core processor range, which ensures that users can manage demanding applications and multitask efficiently. Alongside this, the device typically comes equipped with ample RAM, providing speed and responsiveness that enhances productivity.

Moving to the ThinkPad 4223, it streamlines user experience with advanced connectivity options. The inclusion of multiple USB ports, HDMI, and Ethernet capabilities allows for seamless integration with various devices and networks. The 4223 model often houses a backlit keyboard, enabling users to work effortlessly in low-light environments. This model puts a strong emphasis on portability, making it a reliable companion for professionals on the move.

The ThinkPad 4229 takes connectivity a step further by offering options like Wi-Fi 6 and Bluetooth, ensuring fast and stable connections whether in the office or on the go. This model is often equipped with a higher resolution display, contributing to a better viewing experience for video conferencing and presentations. Its extended battery life is a notable feature, allowing users to remain productive without the constant need for recharging.

All three models in the 422x series boast Lenovo’s robust security features, including fingerprint readers and TPM (Trusted Platform Module), which safeguard sensitive data against unauthorized access. Furthermore, the reputation of Lenovo ThinkPads for their exceptional keyboard layout ensures that users can type comfortably over extended periods, reducing strain and increasing efficiency.

In summary, the Lenovo ThinkPad 4228, 4223, and 4229 models represent a blend of power, durability, and user-friendly design. With their focus on connectivity, performance, and security, these laptops cater perfectly to the needs of professionals and businesses, confirming Lenovo's status as a leading manufacturer in the world of computing technology. Whether you need a rugged workhorse for heavy tasks or a portable device for meetings, the ThinkPad series provides versatile solutions to meet any requirement.