User`s manual

the cells provide a visual representation of the variation in : -
process (see Cell).
Individuals - Individual observations or results (X).
LCL - The lower control limit (see Control limits).
LSL - The lower specification limit (see Specification).
Mean - The arithmetic average of a series of values (X
bar).
Non-conforming units - Units that do not conform to a
specification or other inspection standard. Sometimes
called defective or discrepant units.
p - The fraction of non-conforming (or defective) units
produced by a process.
Population - All of the units produced by a process (see
Sample).
Process - The combination of machines, materials,
procedures, people, and environment that result in a given
-
product or service.
Process capability - A measure of the uniformity of
product that a process is capable of producing. It is
expressed numerically by Cp, Cr, and Cpk. Using these
measures requires the process to be in control (within
control limits) and the process distribution to be normal
(bell-shaped). A process is “capable” when the dispersion
of the process distribution is less than the total specification
tolerance, and lies within both specification limits.
R bar-The mean range of the subgroups.
R - The range, or difference, between the maximum and
minimum values in a subgroup.
Sample - Part of the population of units produced by a
process (see Population). A subgroup.
SLS - The Allen-Bradley Smart Linear Sensor.
SPC - Means “Statistical Process Control,” and refers to
-
the use of statistical techniques, such as control charts, to
analyze the results of a process in order to control the
process and ensure that its results are acceptable. The
objective of SPC is to achieve process results that are
always within the specification limits.
Specification - The engineering requirement used to
evaluate the acceptability of each item produced by a
process. A specification defines a nominal or “target” value
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