- Objective 3.1: Identify the various types of preventive maintenance measures, products, and procedures and when and how to use them.
- Objective 3.2: Identify various safety measures and procedures and when and how to use them.
- Objective 3.3: Identify environmental protection measures and procedures and when and how to use them.
- Quick Answers
- Answers and Explanations
Objective 3.2: Identify various safety measures and procedures and when and how to use them.
What is the cause of chip creep?
Cyclic variations in temperature
Repeated power surge
When working around electrical equipment including computers, what type of fire extinguisher should be on hand?
What surge-suppressor rating describes how quickly its protective circuitry can react to changes in the incoming line and limit the amount of change that passes through?
The best method of limiting EMI in a PC system is to _______.
wear a wrist strap to protect the system from EMI discharges
properly ground the system using a three-wire power cable
route signal cables and power cables together to cancel induced electrical noise
remove any unused back-panel slot covers to permit EMI to vent from the system unit
Damaging Electrostatic Discharge is most likely to occur when _______.
working around rubber mats
using test instruments on a system
the humidity is low
you accidentally get too close to the power supply unit while it is operating
The most effective grounding system for a microcomputer is _______.
an ESD wrist or ankle strap
the safety ground plug at a commercial AC receptacle
the ground plane of the system board
the chassis ground provided by the brass standoff(s)
When would it be inappropriate to use an ESD wrist strap?
While working on hard disk drives
While working on system boards
While working on CRT video monitors
While working on printers
In terms of maintenance issues, how are the effects of ESD and EMI different?
EMI is not destructive, whereas ESD can be very destructive.
ESD is not destructive, whereas EMI can be very destructive.
EMI improves system efficiency, whereas ESD can be very destructive.
ESD improves system efficiency, whereas EMI can be very destructive.
What type of equipment should be used to minimize the chances of ESD during normal computer maintenance work?
_______ is the gradual deterioration of the electrical connection between the pins of an IC and its socket.
In addition to wearing a wrist grounding strap, what other precaution can you take to prevent ESD discharges?
Remove dust from the equipment and workplace using compressed air.
Install a dehumidifier.
Use Styrofoam sheets on the workbench surface.
Install static-free carpet in the work area.
ESD is most likely to occur when _______.
you unplug a power supply unit
the relative humidity is above 50%
the relative humidity is below 50%
you touch the power supply unit while it is operating
Which voltage level is more dangerous110V AC at 5 amps, or 25,000V DC at 5 microamperes?
25,000V is much more dangerous than 110V.
Neither is particularly dangerous.
Both are extremely dangerous.
5 amps is much more dangerous than 5 microamperes.
Which UPS rating describes how long it can supply power to a given load?
What are the voltage levels commonly found in a CRT?
The local weather report indicates that an electrical storm with severe winds is likely to occur in your area overnight. What reasonable precautions should you take to protect your computers?
Monitor the computers until the storm passes.
Plug the computers into a surge protector.
Turn off the computers.
Unplug the computers.
What is the best device for transporting computer equipment?
A server rack
The original packaging
A sturdy carton filled with Styrofoam peanuts
An antistatic bag
Why is it important that the UPS notifies the host system that a power failure has occurred? (Choose all that apply.)
So that the host computer's operating system can conduct an orderly shutdown of the system
So that the host computer can tell the operator how much time is available before he must shut down the system
So that the host computer's management software can notify an administrator that a problem has occurred
So that the user will stop entering data that might be lost if the power does not come back on before the UPS batteries fail
What is the best tool for releasing the charge on a CRT anode?