Power Fulctuation Types

Question 1

What are the five types of power fluctuation?

Answer 1

Blackout.
Brownout.
Noise.
Spike.
Power Surge.

Question 2

What is a blackout? Potential causes?

Answer 2

Complete loss of AC(Input) power. Could be caused by a blown fuse, damaged transformer or power line.

Question 3

What is a Brownout? When do they occur?

Answer 3

A reduced voltage level of AC power over a long period of time.
Brownouts occur when power lines drop below 80% of the normal voltage level and when electrical circuits are overloaded.

Question 4

What is noise? What are the effects?

Answer 4

Interference from generators and lightning.

Results in poor quality power. This can result in errors in the computer system.

Question 5

What is a spike? How can they occur?

Answer 5

Sudden increase in voltage that lasts for a short period and exceeds 100% of the normal voltage on the line.
They can be caused by lightning strikes, but can also occur when electrical systems come back online after a blackout.

Question 6

What is a power surge?

Answer 6

Dramatic increase in the flow of voltage above the normal flow of the electrical current.
A power surge lasts for a few nanoseconds or a one-billionth of a second.

Question 7

What power protection devices are there?

Answer 7

Surge Protector.
Uninterruptable Power Supply (UPS).
Standby Power Supply (SPS).

Question 8

What is a surge protector?

Answer 8

A device that helps protect against damage from surges and spikes.

Question 9

How do surge protectors work?

Answer 9

A surge suppressor diverts the etxra electrical voltage that is on the line into the ground.
Once its limit is reached however, it will need to be replaced.

Question 10

How are surge protectors measured?

Answer 10

In joules. This measures how much energy they can absorb over time.

Question 11

What is a UPS?

Answer 11

A device that helps protect against elecrtical porblems by supplying a consistent level of electrical power.

Question 12

What is in constant use while using a UPS?

Answer 12

The battery.

Question 13

What can many UPS devices communicate directly with?

Answer 13

The Operating System.

Question 14

What are the benefits of the UPS communicating with the OS?

Answer 14

It allows for the UPS to shut down the computer and save data prior to the UPS losing all battery power.

Question 15

What power fluctuation events are UPS’ useful against?

Answer 15

Brownouts and blackouts. This is becaus rthey provide a consistent level of quality voltage that cannot be interrupted.

Question 16

What should a UPS never be plugged into? Why?

Answer 16

A laser printer. It could overload the UPS.

Question 17

What is a SPS?

Answer 17

A device that helps protect against potential electrical power supply problems by a backup battery to supply power when the incoming voltage drops below the normal level.

Question 18

How do SPS’ work?

Answer 18

When the voltage decreases the battery supplies DC power to a power inverter, which converts it to AC power for the computer to use.

Question 19

Why is a SPS not as reliable as a UPS?

Answer 19

Because of the time it takes to switch over to the battery.

If the switching device fails the battery cannot supply power to the computer.