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INSTRUCTION MANUAL
SGTEL-168
TELECOM LINE SURGE GENERATOR
1912 1 E l T o ro R d
●
Si l vera do, Ca lifo rni a 9 26 76
●
(9 49) 459 -96 00
●
co m-p o wer. com
REV070516
5.4.1.1 Measurement of Voltage Waveform Parameters
This section discusses the measurement process and
calculations for proper determination of the individual
waveform parameter values.
PEAK VOLTAGE (V
pk
)
For positive surges, the Peak Voltage (V
pk
) is the highest
measured voltage value within the envelope of the surge
waveform. For negative surges, the Peak Voltage (V
pk
) is the
lowest measured voltage value within the envelope of the
surge waveform.
RISE TIME (T
r
)
The Rise Time (T
r
) is calculated based on the measurement of
T
,
which is defined below
:
T
=
Time difference between:
(A)
the first point on the rising slope of the
waveform at or above 30% of V
pk
;
and,
(B)
the first point on the rising slope of the
waveform at or above 90% of V
pk
.
T
r
=
1.67 x T
DECAY TIME (T
d
)
The Decay Time (T
d
) [
or fall time
] is determined through
calculation and measurement of the waveform.
T
d
=
Time difference between:
(A)
virtual
origin
**
;
and,
(B)
the first point on the falling slope of the
waveform
at
or
below
50%
of V
pk
.
**
Virtual Origin is shown as the red circle in the graphic to
the left. It is a fictional point at which, ideally, the
waveform begins. It is positioned at ‘zero’ volts and lies on
the same slope as the 30%/V
pk
and 90%/V
pk
points. It is
calculated as follows:
T
virtual-origin
(
(
X
2
-
X
1
)
(
Y
2
-
Y
1
)
(
)
)
X
1
=
*
Y
1
X
1
=
Time @ 30%/V
pk
point
Y
1
=
Voltage @ 30%/V
pk
point
X
2
=
Time @ 90%/V
pk
point
Y
2
=
Voltage @ 90%/V
pk
point
where:
