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1.
Power Failure - A total loss of utility power. Can by caused
by lightnin strikes, downed power lines, grid overdemands, accidents
and natural disasters. |
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2.
Power Sag - Short-term low voltage. Triggered by the startup
of large loads, utility switching, utility equipment failure, lightning
and power service that is too small for the demand. In addition
to system crashes, sags can damage hardware. |
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3.
Power Surge - Also known as a spike. Short-term high voltage
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 damage hardware. |
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4.
Undervoltage - Also known as a brownout. Reduced line voltage
for extended periods ranging from a few minutes to a few days. Can
be caused by an intentional utility voltage reduction to conserver
power during peak demand periods or heavy loads that exceed supply
capacity. |
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5.
Overvoltage - Increased line voltage for extended periods
ranging from a few minutes to a few days. Can be caused by a lightning
strike that sends line voltages to levels in excess of 6,000 volts.
A spike almost always results in data loss and/or hardware damage. |
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6.
Electrical Line Noise - High frequency waveform interference.
Can be caused by either Line RF1 or EMI interference generated by
transmitters, wleding devices, SCR-driven printers and lightning. |
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7.
Frequency Variation - A change in frequency stability,
resulting from generators or small co-generation sites being loaded
and unloaded. Can causse erratic operation, data loss, system crashes
and equipment damage. |
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8.
Switching Transient - Instantaneous undervoltage (nothc).
Normal duration is shorter than a spike and generally falls in the
range of nanoseconds. |
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9.
Harmonic Distortion - Distortion of the normal waveform,
caused by switch-mode power supplies, variable speed motors and
drives, copiers and fax machines and other non-linear loads. Can
result in communication errors, overheating and hardware damage. |
