|
Power
Problem |
Definition
* |
Cause
* |
Solution |
|
Series
3 |
Series
5 |
Series
9 |
|
1
Power Failure |
|
A total loss of
utility power |
Can be caused by a
number of events: lightning strikes, downed power lines, grid
over demands, accidents and natural disasters |
- |
- |
- |
|
2
Power Sag |
 |
Short term low
voltage |
Triggered by the
startup of large loads, utility switching, utility equipment
failure, lighting and power service that's too small for the
demand. In addition to crashes, sags can damage
hardware |
- |
- |
- |
|
3
Power Surge |
 |
Short term high
voltage |
With voltages
above 110% of nominal, surges can be triggered by a rapid
reduction in power loads, heavy equipment being turned off, or
by utility switching. The results can potentially damage
hardware. |
- |
- |
- |
|
4
Brownout |
 |
Reduced line
voltage for extended periods of a few minutes to a few
days |
Can be caused by
an intentional utility voltage reduction to conserve power
during peak demand periods or other heavy loads that exceed
supply capacity. |
- |
- |
- |
|
5
Electrical Line Noise |
 |
High frequency
waveform that piggyback on the line waveform |
Can be caused by
either RFI or EMI interference generated by transmitters,
welding devices, SCR driven printers, lightning etc. |
- |
- |
- |
|
6
High Voltage Spike |
 |
Instant and
dramatic increase in line voltage |
Can be caused by
lightning strike and can send line voltages to levels in
excess of 6,000 volts. A spike almost always results in data
loss or hardware damage. |
- |
- |
- |
|
7
Frequency Variation |
 |
A change in
frequence stability |
Resulting from
generator or small cogeneration sites being loaded and
unloaded. Frequency variation can cause erratic operation,
data loss, system crashes and equipment damage. |
- |
- |
- |
|
8
Switching Transients |
 |
Instantaneous high
voltage increase |
Normal duration is
shorter than a spike and generally falls in the range of
nanoseconds. |
- |
- |
- |
|
9
Harmonic Distortion |
|
Distortion of the
normal waveform generally transmitted by nonlinear
loads |
Switched mode
power supplies, variable speed motors and drives, copiers and
fax machines are examples of non-linear loads. Can cause
communication errors, overheating and hardware
damage. |
- |
- |
- |
