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

Page 18

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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)