CCT Calibration Techniques & Procedures 5

Question 1

A pressure transmitter calibrated at sea level is relocated to an installation at 5,000 feet elevation. For a gauge pressure transmitter, this change will:

Accepted Answer

Shift the zero reading because gauge pressure references local atmospheric pressure

Answer

Gauge pressure is measured relative to local atmospheric pressure; at higher elevation, lower atmospheric pressure causes the zero point to shift, requiring re-zeroing at the new location.

Question 2

During calibration, a technician applies 50% of input range and observes a reading 2% of full scale higher than expected consistently across three trials. This error is best classified as:

Accepted Answer

Systematic error (bias) at mid-scale

Answer

A consistent, repeatable offset at the same input point across multiple trials indicates a systematic bias rather than random scatter or hysteresis.

Question 3

The primary reason calibration procedures specify a stabilization period after changing the input to the unit under test is to:

Accepted Answer

Allow transient responses to decay so the instrument reaches steady-state before reading

Answer

Instruments have response time constants; reading before steady-state is reached introduces a dynamic error that is not representative of the instrument's static accuracy.

Question 4

When calibrating a torque wrench, the applied reference torque is usually generated by hanging calibrated weights at a known distance from the drive axis. The formula used is:

Accepted Answer

T = F × d (where F = weight force, d = moment arm length)

Answer

Torque equals force multiplied by the perpendicular distance (moment arm) from the axis of rotation; T = F × d is the fundamental torque equation.

Question 5

A calibration technician must calibrate a volumetric flask. The gravimetric method determines volume by:

Accepted Answer

Weighing a known mass of water delivered by the flask and dividing by water density at that temperature

Answer

The gravimetric method uses the relationship V = m / ρ, where mass is measured precisely and water density at the measured temperature is obtained from tables to calculate true volume.

(CCT) Certified Calibration Technician Practice Test

(CCT) Certified Calibration Technician Practice Test

CCT Calibration Techniques & Procedures 5