Associated Research HYPOTULTRA III 7620, Operation And Service Manual, Page: 59 / 148

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4.3.2. AC Withstand, Models 7620 and 7650
From the Test Parameter review screen, scroll the highlighted area to the Test Type and press
the “Edit” soft key.
The Test Parameter edit screen will now be displayed. Now press the “Change” soft key until
the letters ACW appear in the parameter field. Press the ENTER key to select the ACW test.
The AC Withstand parameter-review screen will appear as follows:
T e s t T y p e A C W R a m p U P 9 9 9 . 9 s
V o l t a g e X X X V D w e l l 9 9 9 . 9 s
^
M a x L m t T x x . x x m A R a m p D N 9 9 9 . 9 s
M i n L m t T x x . x x m A F r e q u e n c y 6 0 H z
v
M a x L m t R x x . x x m A A r c D e t e c t O F F
M i n L m t R x x . x x m A A r c S e n s e 5
< >
D i s p l a y T o t a l C o n t i n u i t y O F F
C o n n e c t O N < m o r e >
E d i t
T e s t T y p e = A C W
P r e v
N e x t
C h a n g e
The second or <more> screen will only appear if there is a scanner selection in the menu. The
Scanner selections will only appear if there is a scanner installed or an external scanner
connected to the instrument. This is an auto detect feature in hardware.
From the AC Withstand setting screen the following parameters may be selected for editing:
Voltage, Max-Lmt T, Min-Lmt T, Max-Lmt R, Min-Lmt R, Display Total/Real, Connect, Ramp
Up, Dwell Time, Ramp Down, Frequency, Arc Detect (ON/OFF), Arc Sense, Continuity
selection (DC continuity or OFF), Prompt and Scanner Channel selections (if there is a scanner
installed).
Real Current
The AC Real Current function allows the user to monitor only the real portion of the leakage
current and ignore any reactive components due to capacitance in the device under test. It is
important to recognize that the total current is the vector sum of the reactive and real current,
not the direct addition of the two components. As in a right triangle, the total current is the
square root of the sum of the squares of the real and reactive currents.
Since the real component is usually much smaller than the reactive current, a doubling of the
real current increases the total current by only a small amount. Unless the two components are