Equipment Calibration & Diagnostics Flashcards
7 cards from real CMO practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Equipment Calibration & Diagnostics flashcards as text
A Mobilyze operator calibrates a flow meter and finds the 'as-found' reading is within tolerance. What is the correct action?
Answer: Document the as-found reading and return the instrument to service without adjustment
If the as-found reading is within tolerance, no adjustment is needed; the result is documented and the instrument is returned to service without alteration.
Which symptom most strongly suggests a Mobilyze encoder has lost its reference (home) position?
Answer: Erratic or absolute position drift after power cycling
Absolute position drift or incorrect position after power cycling indicates the encoder's reference point has been lost, requiring re-homing.
What is the effect of performing calibration outside the specified temperature range of the instrument?
Answer: Thermal expansion and sensor response changes may introduce errors into the calibration
Temperature affects sensor response characteristics, material dimensions, and electronics, so calibrating outside the specified range introduces errors not present under normal operating conditions.
A Mobilyze diagnostic readout shows 'ADC Saturation' on a sensor channel. What does this indicate?
Answer: The analog-to-digital converter is receiving a signal beyond its measurable input range
ADC saturation means the input voltage exceeds the converter's maximum range, producing clipped or maximum output values and making accurate measurement impossible.
During vibration diagnostics on a Mobilyze platform, an FFT spectrum shows a dominant peak at exactly twice the shaft rotation frequency. This is typically associated with:
Answer: Misalignment
A dominant vibration peak at 2× rotational frequency (2X) is a classic signature of shaft or coupling misalignment.
Why is it important to allow warm-up time before performing calibration on electronic measurement instruments?
Answer: To allow internal components to reach thermal equilibrium, stabilizing their electrical characteristics
Electronic components change their resistance and gain characteristics as they heat up; warm-up time ensures stable, repeatable readings during calibration.
A Mobilyze system uses a 4–20 mA current loop for sensor signals. A reading of 2 mA most likely indicates:
Answer: An open-circuit fault in the wiring or sensor
In a 4–20 mA loop, 4 mA represents the live zero (minimum range); any signal below 4 mA, such as 2 mA, indicates a wiring break or sensor failure (open circuit).