220-1102 Question 729
Single answerPower surges, brownouts, and blackoutsA small accounting office experiences frequent utility power problems during summer storms. Users report that desktop PCs randomly reboot when the building lights dim, and one workstation was damaged after a lightning-related event. The office manager wants a solution that will keep users working through brief outages and also protect equipment from unstable voltage conditions. Which device should the technician recommend?
- A
A basic power strip with a built-in circuit breaker
- B
A surge protector rated for transient voltage suppression only
- C
An uninterruptible power supply (UPS) with battery backup and line conditioning/automatic voltage regulation
- D
A replacement computer power supply with a higher wattage rating
Show answer and explanation
Correct answer: C
Explanation
The best recommendation is a UPS with battery backup and AVR/line conditioning because the scenario includes all three major utility power issues: surges, brownouts, and blackouts. Surge protectors are useful for transient overvoltage events, but they do not maintain power during outages or correct low-voltage conditions. A UPS is the standard best-practice recommendation for business workstations and critical devices when continuity and power quality both matter. In CompTIA A+ objectives, candidates are expected to distinguish among surges, brownouts, and blackouts and choose the appropriate protection method. Manufacturer documentation from major UPS vendors such as APC and Eaton commonly describes AVR as a feature that boosts or trims voltage during brownout/overvoltage conditions while reserving battery power for actual outages.
- A. Incorrect.
This is incorrect. A basic power strip may provide additional outlets and overload protection through a circuit breaker, but it does not provide battery backup for blackouts and typically does not correct low-voltage brownout conditions. It also should not be assumed to provide meaningful surge protection unless specifically rated for it.
- B. Incorrect.
This is incorrect. A surge protector can help reduce damage from brief voltage spikes or surges, such as those associated with lightning or utility switching events, but it does not keep systems running during a blackout and does not address sustained undervoltage conditions that occur during brownouts. This option solves only part of the problem.
- C. Correct.
This is correct. A UPS with battery backup allows users to continue working during short blackouts and gives systems time for proper shutdown during longer outages. A model with line conditioning or automatic voltage regulation (AVR) also helps compensate for brownouts and other unstable voltage conditions without immediately switching to battery power. Many UPS units also include surge suppression, making this the most complete solution for the scenario.
- D. Incorrect.
This is incorrect. Replacing the internal power supply with a higher wattage unit does not protect against external power anomalies such as surges, brownouts, or blackouts. Wattage capacity only relates to how much power the PC can supply to internal components, not to conditioning incoming utility power.