Appx.8
Event Detection Methods
Appx. 4 Event Detection Methods
Transient overvoltage
Measurement method
Transient overvoltage event is detected when the waveform obtained by eliminating the
fundamental component (50 Hz/60 Hz) from a waveform sampled at 200 kHz exceeds a threshold
value specied as an absolute value.
Detection occurs once for each the fundamental voltage waveform, and voltages of up to ±2,200 V
can be measured.
Recorded data
Transient voltage value Waveform peak value during 3 ms period after elimination of fundamental
component
Transient width Period during which threshold value is exceeded (2 ms max.)
Max. transient voltage value Max. peak value of waveform obtained by eliminating the fundamental
component during the period from transient IN to transient OUT (leaving
channel information)
Transient period Period from transient IN to transient OUT
Transient count during
period
Number of transients occurring during period from transient IN to transient
OUT
(Transients occurring across all channels or simultaneously on multiple
channels are counted as 1)
Transient waveform
(Available after the rmware
update)
Transient waveform
Sampled waveform
200 kHz
Threshold
Transient voltage
Transient width
Event IN
1 ms 2 ms
Elimination of fundamental
component (5 kHz or less)
Transient waveform
with fundamental
component
eliminated (5 kHz or
less)