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Quick Results Guide
Varistor alpha
Determines ALPHA (
α
), which is the logarithmic ratio of two voltage measurement points
on a non-linear V-I curve.
where: V1 is the voltage measurement at the first I-Source point (I1).
V2 is the voltage measurement at the second I-Source point (I2).
The log (x) function uses the absolute value of x.
Use the following menu sequence to configure and enable the varistor alpha math function:
Press CONFIG > press FCTN > select VAR ALPHA
After selecting VAR ALPHA, you will be prompted to enter the two I-Source values.
This math function can now be selected by pressing the FCTN key.
Percent deviation
This calculation provides the percent deviation between the normal display reading and the
user specified reference value:
% Deviation =
where:
X is the normal display measurement reading.
Y is the reference value.
The reference value (Y) can be a user-specified value or a reading acquired by the
SourceMeter.
Use the following menu sequence to configure and enable the percent deviation math
function:
Press CONFIG > press FCTN > select %DEV
After selecting %DEV you will be prompted to set the reference value. Either key in the ref-
erence value, or (with the output on) press the AUTO key to trigger a measurement. The mea-
sured reading will be displayed as the reference.
Limit testing – After the reference value is entered, you will be prompted to enter high and
low tolerances (in %) for the reference value. These tolerances set the high and low limits for
Limit 2 test. For example, if the reference value is 1k
Ω
and the high and low tolerances are 5%,
the high limit for Limit 2 test will be 1050
Ω
and the low limit will be 950
Ω
.
This math function can now be selected by pressing the FCTN key. The percent deviation
and the result of the limit test (PASS or FAIL) will be displayed.
α
log I2 I1
⁄
(
)
log V2 V1
⁄
(
)
-------------------------------
=
X
Y
–
(
)
Y
-------------------
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