Measurement Evaluation System Print E-mail

For quality, process control and improvement projects it is an absolute necessity to know what you are doing. An evaluation has to take place to see how reliable these measurements are.

When to use

Before starting investigations in production process. Keep the set specifications in mind and test reference products. These reference products can always be re-evaluated when there are doubts about the measuring system.

Measurement Evaluation System can be used:
  • when new measuring devices need to be evaluated
  • when new people come at the measuring department

Description

The measurement uncertainties are build up from three different aspects:
  • resolution
  • systematic deviation
  • random deviation

Resolution

Resolution is the smallest unit of a measurement. A rule of thumb is that resolution should be 10x as small as the difference between upper and lower limit.

 

Systematic deviation

The systematic deviation is the average of an infinite number of measurements and the actual value. The actual value is determined by a measuring system of a higher order.

 

Random deviation

The random deviation is the difference in a group of measurements. The differences can be caused by the measuring system, the environment and the people that use the system.