CST CST Data Communications & Indicator Systems 1 — Questions and Answers
Question 1: What is the primary function of a scale indicator in a weighing system?
- Print weight tickets automatically
- Convert the load cell signal into a human-readable weight display (Correct answer)
- Supply excitation voltage to the load cell only
- Control conveyor belt speed based on weight
Correct answer: Convert the load cell signal into a human-readable weight display
A scale indicator converts the analog or digital signal from the load cell into a human-readable weight display on the operator interface.
Question 2: What does 'span' calibration adjust in a scale indicator?
- The zero balance point with no load
- The full-scale output range by applying a known reference weight (Correct answer)
- The overload alarm threshold
- The tare memory register
Correct answer: The full-scale output range by applying a known reference weight
Span calibration sets the full-scale output range by applying a known test weight and adjusting the indicator's gain to read the correct value.
Question 3: What is a 'division' (d) on a certified scale?
- The number of load cells in a scale system
- The smallest increment of weight displayed by the scale (Correct answer)
- The total capacity divided by the number of load cells
- The interval between required calibration checks
Correct answer: The smallest increment of weight displayed by the scale
A division (d) is the smallest increment of weight displayed on a scale, determined by the scale's accuracy class and resolution.
Question 4: What does a 'multi-interval' scale do differently than a standard single-range scale?
- It uses multiple load cells for redundancy
- It automatically uses finer divisions at lower weight ranges and coarser divisions at higher ranges (Correct answer)
- It can operate in multiple countries with different units
- It stores multiple tare weights simultaneously
Correct answer: It automatically uses finer divisions at lower weight ranges and coarser divisions at higher ranges
A multi-interval scale switches to finer graduation sizes at lower weight ranges and coarser sizes at higher ranges, improving accuracy across its full capacity.
Question 5: What is the purpose of the tare function on a scale indicator?
- To reset the span calibration to factory defaults
- To subtract the container weight so only the net contents weight is displayed (Correct answer)
- To print the current weight to a connected printer
- To perform an automatic zero tracking adjustment
Correct answer: To subtract the container weight so only the net contents weight is displayed
The tare function zeros out the weight of an empty container so only the net weight of its contents is displayed on the indicator.
Question 6: Which display technology is most commonly used in modern commercial scale indicators?
- Analog needle and dial gauge
- Nixie tube numeric display
- LCD or LED digital display (Correct answer)
- Mechanical drum counter
Correct answer: LCD or LED digital display
Modern scale indicators predominantly use LCD or LED digital displays for their clarity, low power consumption, durability, and ease of reading.
CST CST Data Communications & Indicator Systems 1
What is the primary function of a scale indicator in a weighing system?