How is accuracy defined for test instruments?

Accuracy for test instruments is defined as how close the measurement is to the actual value. This is a fundamental concept in instrumentation and process control, as accuracy reflects the ability of an instrument to provide readings that are true representations of the quantity being measured.

When discussing accuracy, it is essential to differentiate it from other characteristics. For example, an instrument might be reliable in terms of consistently providing measurements over time, but that does not necessarily mean those measurements are accurate. Similarly, maximum output ratings or cost do not directly relate to an instrument's ability to measure accurately. The focus on the proximity of the measured value to the real value is what sets the definition of accuracy apart and underscores its importance in ensuring quality and precision in measurements and control processes.