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a static shock and immediately generates a "No POST/No Video" symptom with a beep code that is emitted for missing or
nonfunctional memory.
● Intermittent – Intermittent failures represent approximately 80 percent of ESD-related failures. The high rate of intermittent
failures means that most of the time when damage occurs, it is not immediately recognizable. The DIMM receives a static shock,
but the tracing is merely weakened and does not immediately produce outward symptoms that are related to the damage. The
weakened trace may take weeks or months to melt, and in the meantime may cause degradation of memory integrity, intermittent
memory errors, and so on.
The more difficult type of damage to recognize and troubleshoot is the intermittent (also called latent or "walking wounded") failure.
Perform the following steps to prevent ESD damage:
● Use a wired ESD wrist strap that is properly grounded. The use of wireless anti-static straps is no longer allowed; they do not
provide adequate protection. Touching the chassis before handling parts does not ensure adequate ESD protection on parts with
increased sensitivity to ESD damage.
● Handle all static-sensitive components in a static-safe area. If possible, use anti-static floor pads and workbench pads.
● When unpacking a static-sensitive component from its shipping carton, do not remove the component from the anti-static
packing material until you are ready to install the component. Before unwrapping the anti-static packaging, ensure that you
discharge static electricity from your body.
● Before transporting a static-sensitive component, place it in an anti-static container or packaging.
ESD field service kit
The unmonitored Field Service kit is the most commonly used service kit. Each Field Service kit includes three main components:
anti-static mat, wrist strap, and bonding wire.
Components of an ESD field service kit
The components of an ESD field service kit are:
● Anti-Static Mat – The anti-static mat is dissipative and parts can be placed on it during service procedures. When using an
anti-static mat, your wrist strap should be snug and the bonding wire should be connected to the mat and to any bare metal on
the computer being worked on. Once deployed properly, service parts can be removed from the ESD bag and placed directly on
the mat. ESD-sensitive items are safe in your hand, on the ESD mat, in the computer, or inside a bag.
● Wrist Strap and Bonding Wire – The wrist strap and bonding wire can be either directly connected between your wrist and
bare metal on the hardware if the ESD mat is not required, or connected to the anti-static mat to protect hardware that is
temporarily placed on the mat. The physical connection of the wrist strap and bonding wire between your skin, the ESD mat,
and the hardware is known as bonding. Use only Field Service kits with a wrist strap, mat, and bonding wire. Never use wireless
wrist straps. Always be aware that the internal wires of a wrist strap are prone to damage from normal wear and tear, and must be
checked regularly with a wrist strap tester in order to avoid accidental ESD hardware damage. It is recommended to test the wrist
strap and bonding wire at least once per week.
● ESD Wrist Strap Tester – The wires inside an ESD strap are prone to damage over time. When using an unmonitored kit, it is a
best practice to regularly test the strap prior to each service call, and at a minimum, test once per week. A wrist strap tester is the
best method for doing this test. If you do not have your own wrist strap tester, check with your regional office to find out if they
have one. To perform the test, plug the wrist-strap's bonding-wire into the tester while it is strapped to your wrist and push the
button to test. A green LED is lit if the test is successful; a red LED is lit and an alarm sounds if the test fails.
● Insulator Elements – It is critical to keep ESD sensitive devices, such as plastic heat sink casings, away from internal parts that are
insulators and often highly charged.
● Working Environment – Before deploying the ESD Field Service kit, assess the situation at the customer location. For example,
deploying the kit for a server environment is different than for a desktop or laptop environment. Servers are typically installed
in a rack within a data center; desktops or laptops are typically placed on office desks or cubicles. Always look for a large open
flat work area that is free of clutter and large enough to deploy the ESD kit with additional space to accommodate the type of
computer that is being repaired. The workspace should also be free of insulators that can cause an ESD event. On the work area,
insulators such as Styrofoam and other plastics should always be moved at least 12 inches or 30 centimeters away from sensitive
parts before physically handling any hardware components.
● ESD Packaging – All ESD-sensitive devices must be shipped and received in static-safe packaging. Metal, static-shielded bags
are preferred. However, you should always return the damaged part using the same ESD bag and packaging that the new part
arrived in. The ESD bag should be folded over and taped shut and all the same foam packing material should be used in the
original box that the new part arrived in. ESD-sensitive devices should be removed from packaging only at an ESD-protected
work surface, and parts should never be placed on top of the ESD bag because only the inside the bag is shielded. Always place
parts in your hand, on the ESD mat, in the computer, or inside an anti-static bag.
● Transporting Sensitive Components – When transporting ESD sensitive components such as replacement parts or parts to be
returned to Dell, it is critical to place these parts in anti-static bags for safe transport.
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