1-38
IM 253710-01E
Example of an equation used to display the TREND waveform of Umn of element 1
and the waveform
Equation: TRENDM(C1)
Signal under
computation
Trend waveform
Synchronizing
signal
When the rising slope of the
synchronizing signal less than two
When the rising slope of the
synchronizing signal is two or more
No trend waveform
Measurement/Computation period
AVG
The rms values of voltage and current and the instantaneous value (sampled data) of
active power can be exponentially averaged using a specified attenuation constant
and the waveform can be displayed. The items are averaged according to the
following equation.
Example of an AVG function
AVG(C1
∗
C2) : Displays the AVG waveform of the active power of element 1.
x
n
=
(d
n
– x
n
–1
)
k
x
n–1
+
x
n
: Displayed value at the nth time. (The displayed value of x
1
on the first time is d
1
.)
x
n–1
: Display value at the n–1 time that has been exponentially averaged.
d
n
: Sampled data at the nth time.
k : Attenuation constant (Select 2, 4, 8, 16, 32, or 64)
d1
d3
x1
(= d1)
Signal being
computed
d2
d4
d5
x2
x3
x4
x5
Exponential average
of x1 and d2
Exponential average
of x2 and d3
Exponential average
of x3 and d4
Exponential average
of x4 and d5
AVG waveform
1.8 Waveform Analysis
