CST Weights & Measures Certification 2

Question 1

What is the maximum allowable error (MAE) for a Class III commercial scale used at a retail checkout with a capacity of 30 lb?

Accepted Answer

±0.02 lb

Answer

NIST Handbook 44 specifies that Class III scales have an MAE of one scale division, and a 30 lb capacity Class III scale typically has 0.01 lb divisions making the MAE ±0.01 lb at the zero end, but ±0.02 lb across mid-range divisions — 0.02 lb is the standard mid-range MAE.

Question 2

Under NIST Handbook 44, which test is used to evaluate a scale's ability to return to zero after loading and unloading?

Accepted Answer

Return-to-zero test

Answer

The return-to-zero test verifies that a scale's indication returns to zero (or the initial no-load reading) after a load is applied and removed.

Question 3

A weights and measures inspector finds a scale with a 'Cardinal' brand name on the nameplate but no NTEP Certificate of Conformance number. What is the appropriate action?

Accepted Answer

Verify if the scale model appears on the NTEP Approved Products List

Answer

An inspector should check the NTEP (National Type Evaluation Program) database to confirm whether the specific model is type-approved, as the absence of a CC number on the plate does not automatically mean the device is non-compliant.

Question 4

Which of the following statements about tare on a commercial scale is correct under Handbook 44?

Accepted Answer

Tare capability must not exceed the scale's capacity

Answer

Handbook 44 requires that the tare mechanism cannot set a tare value beyond the scale's maximum capacity, ensuring the net weight indication remains meaningful.

Question 5

What does the term 'scale division value (d)' refer to in metrology?

Accepted Answer

The smallest unit of measurement the scale can display

Answer

The scale division value (d) is the value of the smallest increment displayed or printed by the indicating or recording element of a scale.

(CST) Certified Scale Technicians Practice Test

(CST) Certified Scale Technicians Practice Test

CST Weights & Measures Certification 2