E – 17, Process capability, Probability distribution – CITIZEN SRP-285N User Manual
Page 18

E – 17
File name : CBM_SR285,A_HDBSR285T19_English.doc
version : 2010/04/26
Σ
x
2
or Σy
2
Sum of all x
2
values or y
2
values
Σ
x y
Sum of (x
z
y) for all x-y pairs
Process capability
Step : ( See Example 53~54. )
1. Press [ DATA ] and there are three menus : DATA–INPUT,
LIMIT–SET, DISTR. Please select LIMIT–SET and press
[
].
2. Enter an upper spec. limit value ( X USL or Y USL), then
press [ ].
3. Enter a lower spec. limit value ( X LSL or Y LSL ), then
press [
].
4. Enter the datasets you want under DATA–INPUT mode.
5. Press [ 2nd ] [ STATVAR ] and scroll through the statistical
results menu by [ ] or [ ] to find out process capability
variables you want. ( See table below )
Variable
Meaning
Cax or Cay
Capability accuracy of the x values or y values
,
Cpx or Cpy
Potential capability precision of the x values or y
values,
,
Cpkx or Cpky Minimum (C
PU
, C
PL
) of the x values or y values,
where C
PU
is upper spec. limit of capability
precision and C
PL
is lower spec. limit of
capability precision
C
pkx
= Min (C
PUX
, C
PLX
) = C
px
(1 – C
ax
)
C
pky
= Min (C
PUY
, C
PLY
) = C
py
(1 – C
ay
)
(Note) : When calculating process capability in 2–VAR mode, the
x
n
and y
n
are independent with each other.
Probability distribution
Step : ( See Example 55. )
1. Based on the datasets in 1–VAR mode, press [ DATA ] and
there are three menu : DATA–INPUT, LIMIT–SET, DISTR.
Please choose DISTR and press [
].
2. Enter a a
x
value, then press [
].
3. Press [ STATVAR ] and scroll through the statistical results
menu by [ ] or [ ] to find out probability distribution
variables you want. (See table below)