CCT Tools & Equipment Operation 2 — Questions and Answers
Question 1: When using a torque wrench for calibration fixture assembly, which practice ensures measurement integrity?
- Apply torque in one continuous motion to the specified value (Correct answer)
- Tighten past the specified value then back off slightly
- Apply torque incrementally in multiple passes
- Use the torque wrench in both clockwise and counterclockwise directions equally
Correct answer: Apply torque in one continuous motion to the specified value
Applying torque in one smooth, continuous motion prevents binding and ensures the reading reflects the actual torque applied to the fastener.
Question 2: A digital multimeter displays 'OL' when measuring resistance. What does this indicate?
- The circuit has zero resistance
- The resistance is below the selected range
- The resistance exceeds the selected measurement range (Correct answer)
- The meter battery is low
Correct answer: The resistance exceeds the selected measurement range
'OL' (overload) means the measured resistance is beyond the meter's selected range, and a higher range should be selected.
Question 3: Which instrument is most appropriate for verifying the flatness of a granite surface plate used as a calibration reference?
- Coordinate measuring machine (CMM)
- Autocollimator (Correct answer)
- Laser interferometer
- Electronic level
Correct answer: Autocollimator
An autocollimator is the standard tool for measuring angular deviations across a surface plate to verify its flatness specification.
Question 4: When calibrating a pressure gauge using a deadweight tester, the weights must be rotated during the test. Why?
- To generate heat that stabilizes the fluid
- To reduce friction effects in the piston-cylinder assembly (Correct answer)
- To ensure the gauge pointer does not stick
- To mix the hydraulic fluid for uniform density
Correct answer: To reduce friction effects in the piston-cylinder assembly
Rotating the weights reduces the effects of static friction between the piston and cylinder, producing a more accurate pressure reference.
Question 5: A thermocouple calibration bath is set to 200°C but reads 198.5°C on the reference probe. What is the bath's temperature error?
- +1.5°C
- -1.5°C (Correct answer)
- +0.75%
- -0.75%
Correct answer: -1.5°C
The bath is 1.5°C below the set point (198.5 - 200 = -1.5°C), so the temperature error is -1.5°C.
Question 6: Which feature of a oscilloscope is most critical when calibrating fast-rise-time pulse generators?
- Vertical sensitivity range
- Bandwidth specification (Correct answer)
- Input impedance value
- Sweep time accuracy
Correct answer: Bandwidth specification
Bandwidth determines the oscilloscope's ability to accurately display fast-rising signals; insufficient bandwidth causes the displayed rise time to appear slower than actual.
Question 7: When zeroing a dial indicator before a calibration measurement, the technician should apply the zero adjustment:
- After removing the indicator from its mounting
- With the spindle at mid-travel and the anvil lightly loaded (Correct answer)
- Only at the beginning of a measurement session
- With the spindle fully extended
Correct answer: With the spindle at mid-travel and the anvil lightly loaded
Zeroing at mid-travel with light load ensures the instrument operates in its most linear region and avoids spindle end-of-travel effects.
CCT Tools & Equipment Operation 2
When using a torque wrench for calibration fixture assembly, which practice ensures measurement integrity?