ST2516 Series Operation Manual
16
value of results for multiple measurements, the PASS/FAIL rate and some engineering coefficients.
Details are as below.
3.4.1
Edge Mode and Settings of Its Relevant Values
Touch this key, two modes is available: ABS (high and low limits) and % (percent error mode).
When ABS is selected, the adjacent two items on the same line will be high and low limits. Touch
them to set the values. When % is selected, the two items on the same line will be nominal value
and percent. Touch them to set the values.
3.4.2
Status ON/OFF
Status ON/OFF:
(1)
When ON is selected, except the trigger button, no other keys and buttons could be enabled.
The instrument makes a statistic at every trigger.
(2)
When OFF is selected, the statistic function will be turned off and other keys and buttons is
available.
3.4.3
Parameters of Statistic Analysis
1)
X
: Average value. Corresponding formula:
x
x
n
=
∑
2)
σ
: Population Standard Deviation. Corresponding formula:
2
2
x
nx
n
σ
−
=
∑
（
=
n
σ
）
3)
s
: Sample Standard Deviation. Corresponding formula:
2
2
1
x
nx
s
n
−
=
−
∑
（
=
1
n
σ
−
）
4)
p
C
: Process Capability Index (Dispersion). Corresponding formula:
|
|
6
p
Hi Lo
C
s
−
=
5)
p
C K
: Process Capability Index (Deviation). Corresponding formula:
|
| |
2 |
6
p
Hi Lo
Hi Lo
x
C K
s
−
−
+
−
=
---------------------------------------------------------------------------------------------------------------------------------
NOTE: Explanations for variables in formulas from 1) to 5):
n
: The total measurement times that a sample is used to make statistic analysis, which
corresponds to the value of TIMES.
x
: Measurement results of each sample measurement. The data are saved in the
