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FAQ
What is Voltage Sag?
Voltage Sag and Voltage dip have the same meaning.
Voltage Sag(Voltage drop) means the short drop of voltage caused by a fault in
the system, short circuit, operation of the transformer or overload. It is the
most common but most important electrical power quality problem. According to
the IEEE standard(IEEE Std. 1159, 1995), Voltage Sag(Voltage drop) is defined
as rms voltage decrease of from 0.1 to 0.9 per unit(pu) within the duration of
1 minute in 0.5 cycle.