Repeatability & Linearity Testing Flashcards
7 cards from real CST practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Repeatability & Linearity Testing flashcards as text
Which type of load cell construction typically exhibits the best linearity performance?
Answer: Full Wheatstone bridge with four active strain gauges
A full Wheatstone bridge with four active gauges provides temperature compensation and the highest linearity because bridge imbalance errors cancel out.
A technician is evaluating a scale where every fifth test shows a reading that is 3 divisions higher than the others. This is best characterized as:
Answer: An intermittent fault causing periodic repeatability failure
A consistent outlier every fifth reading suggests an intermittent condition (loose connection, intermittent binding, electrical noise) causing periodic repeatability failure.
For a Class IIIL (livestock) scale, which environmental factor is most likely to affect both repeatability and linearity test results?
Answer: Animal movement and vibration during measurement
Animal movement introduces dynamic forces that create variability in readings, directly degrading both repeatability and the ability to obtain stable linearity test readings.
During linearity testing, a technician notices the scale reads correctly at zero and full scale but reads 2d high at mid-range. The correction requires adjusting the:
Answer: Linearity or mid-range adjustment
An error at mid-range with correct zero and span readings indicates a linearity (curvature) error that requires a dedicated mid-range or linearity adjustment.
A technician is documenting a repeatability test. Which statistical measure is most appropriate to report as the repeatability error?
Answer: Range (max minus min) of all readings
Repeatability error in weights and measures is conventionally reported as the range (max − min) of repeated readings, per NIST HB 44 and OIML guidelines.
A retail pharmacy scale used to weigh prescriptions must meet which accuracy class requiring the tightest linearity tolerances?
Answer: Class I
Prescription pharmacy scales fall under Class I (precision), which has the most stringent linearity and accuracy requirements due to the safety-critical nature of the application.
When a scale exhibits hysteresis, repeating a linearity test using only ascending loads will:
Answer: Underreport the total error because only one loading path is evaluated
Testing with ascending loads only captures one path of the hysteresis loop, so the full hysteresis error — which requires comparing ascending and descending readings — is not revealed.