CST Environmental Factors & Scale Performance Flashcards
6 cards from real CST practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 CST Environmental Factors & Scale Performance flashcards as text
How does a significant temperature change typically affect a load cell's output reading?
Answer: It causes a shift in both zero and span due to thermal expansion and changes in strain gauge sensitivity
Temperature changes cause thermal expansion in the load cell body and alter the piezoresistive sensitivity of the strain gauges, shifting both the zero balance and span calibration.
What is the purpose of a temperature compensation circuit built into a load cell?
Answer: To minimize the effect of temperature changes on the load cell's output signal accuracy
Temperature compensation circuits use thermistors or precision resistor networks to counteract zero and span shifts caused by temperature changes, maintaining accuracy across the specified temperature range.
What is the typical operating temperature range specified for most commercial industrial scale load cells?
Answer: -10°C to +40°C
Most commercial scale load cells are specified for -10°C to +40°C operating range, covering typical indoor and outdoor commercial environments without extreme cold storage or high-heat industrial conditions.
How should a scale be handled after being moved from a cold storage area to a warm room before calibration?
Answer: Allow the scale to fully acclimate to the ambient temperature before calibrating
Allowing the scale to acclimate prevents thermal gradients within the load cell from causing temporary measurement errors that would result in an inaccurate calibration.
What effect does direct sunlight have on an outdoor truck scale platform during summer operation?
Answer: Uneven thermal expansion of the steel platform stresses load cells and shifts zero readings
Direct sunlight heats the steel platform unevenly, causing differential thermal expansion that introduces stress on the load cells and shifts the zero reading on outdoor truck scales.
What is 'thermal zero drift' as specified in a load cell datasheet?
Answer: The gradual shift in the zero output reading per degree of temperature change
Thermal zero drift is the change in the load cell's zero output per degree of temperature change, expressed as a temperature coefficient in the load cell's specification datasheet.