220-1102 Question 706
Single answerElectrostatic discharge (ESD) strapsA technician is replacing memory modules in a desktop PC on a workbench in a dry office environment. The technician puts on an ESD wrist strap before opening the case. To reduce the risk of electrostatic discharge damage while working inside the computer, where should the technician connect the strap?
- A
To an unpainted metal part of the computer chassis or an approved grounding point
- B
To the plastic front bezel so the strap does not touch metal components
- C
To a power strip surge protector to absorb static before it reaches the PC
- D
To a painted section of the case because paint prevents accidental short circuits
Show answer and explanation
Correct answer: A
Explanation
The best practice when using an ESD wrist strap is to connect it to a known good ground, such as an unpainted metal part of the computer chassis or an approved grounding point on an ESD mat or workstation. The goal is not to 'drain' large amounts of electricity, but to keep the technician, tools, and equipment at the same electrical potential so sensitive components such as RAM are not damaged by a static discharge. This aligns with standard PC repair safety practices commonly taught for CompTIA A+ and with general ESD control guidance used in electronics service environments.
- A. Correct.
Correct. An ESD wrist strap should be connected to a proper ground, commonly an unpainted metal portion of the chassis or another approved grounding point in the work area. This helps equalize electrical potential between the technician and the system, which is the purpose of the strap during service work.
- B. Incorrect.
Incorrect. Plastic is not an appropriate grounding point because it is not conductive. A common misconception is that attaching the strap anywhere on the computer is sufficient, but the strap must connect to a conductive grounded surface to dissipate static safely.
- C. Incorrect.
Incorrect. A surge protector is designed to protect equipment from voltage spikes on the power line, not to serve as the attachment point for an ESD wrist strap. This option reflects confusion between surge suppression and electrostatic discharge control.
- D. Incorrect.
Incorrect. Paint insulates the metal underneath, so a painted case surface is not a reliable conductive connection point. Some technicians choose painted metal because it appears structurally secure, but it does not provide the proper electrical contact needed for ESD protection.