Using preset values
- Last UpdatedNov 04, 2024
- 2 minute read
When the cl_source for a characteristic or for a QM specification that overrides the characteristic is configured (cl_source = 2) to use preset values, the standard mean and the standard deviation are calculated using the cl_*, lcl_* and ucl_* configured for a characteristic or for a QM specification, and are used to validate the measurements against the control rules configured for a characteristic.
If no preset control limits are given (that is, CL, LCL, UCL is null), the average of data points from the last n samples is considered as the center line, the standard deviation is calculated using the data from the last n samples. If the control limit is only given for one side, that is, either LCL or UCL, the control rule violations are evaluated against that one-sided limit.
The preset limits cannot be configured for the characteristics whose default chart type is set to DPMO. Hence, the control limits and sigma (lower and upper) are calculated from all the data points using the configuration from u-chart.
|
Chart Element |
Std. Dev (Lower) |
Std. Dev (Upper) |
|---|---|---|
|
ix |
cl_ix - lcl_ix / 3 |
ucl_ix - cl_ix / 3 |
|
imr |
cl_imr - lcl_imr / 3 |
ucl_imr - cl_imr / 3 |
|
mr |
cl_mr - lcl_mr / 3 |
ucl_mr - cl_mr / 3 |
|
xbar |
cl_xbar - lcl_xbar / 3 |
ucl_xbar - cl_xbar / 3 |
|
range |
cl_range - lcl_range / 3 |
ucl_range - cl_range / 3 |
|
sigma |
cl_sigma - lcl_sigma / 3 |
ucl_sigma - cl_sigma / 3 |
|
ma |
cl_ma - lcl_ma / 3 |
ucl_ma - cl_ma / 3 |
|
ms |
cl_ms - lcl_ms / 3 |
ucl_ms - cl_ms / 3 |
|
p |
cl_p - lcl_p / 3 |
ucl_p - cl_p / 3 |
|
np |
cl_np - lcl_np / 3 |
ucl_np - cl_np / 3 |
|
c |
cl_c - lcl_c / 3 |
ucl_c - cl_c / 3 |
|
u |
cl_u - lcl_u / 3 |
ucl_u - cl_u / 3 |
|
DPMO |
cl_u - lcl_u / 3 * |
ucl_u - cl_u / 3 * |
