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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
5.4.2.1
Measurement of Current Waveform Parameters
This section discusses the measurement process and calculation
process for proper determination of the individual waveform
parameter values.
PEAK CURRENT
The Peak Current (I
pk
) is the highest measured current value
within the envelope of the surge waveform.
RISE TIME
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 10% of I
pk
;
and,
(B)
the first point on the rising slope of the
waveform at or above 90% of I
pk
.
T
r
=
1.25 x T
DECAY TIME
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 I
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 would begin. It is
positioned at ‘zero’ amps and lies on the same
slope as the 10%/I
pk
and 90%/I
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 @ 10%/I
pk
point
Y
1
=
Current @ 10%/I
pk
point
X
2
=
Time @ 90%/I
pk
point
Y
2
=
Current @ 90%/I
pk
point
where:
