SOLUTION

• A load cell is a transducer.
• It is used to create an electrical signal whose magnitude is directly proportional to the force being measured.
• Various types of load cells include hydraulic load cells, pneumatic load cells, and strain gauge load cells.

Strain Gauge Load Cell

• Strain gauge based load cells have a sensing junction/element that when loaded responds to the load by producing an electrical output.
• The circuitry to convert the response to a quantifiable electrical signal is a configuration known as the Wheatstone bridge.
• Strain-gauge-based load cells are the most commonly used type.
• Strain gauges are made up of a long, thin strip of conductive material arranged in a zigzag manner.
• Load cells typically contain multiple strain gauges aligned and wired in a Wheatstone bridge circuit.
• When stress is applied to a strain gauge, the resistance of the strain gauge changes and unbalances the Wheatstone bridge, resulting in a signal output (voltage) that is proportional to the stress.

• The rated capacities of strain-gauge load cells range from 1 N to more than 50 MN, and they can be used with high-resolution digital indicators as force transfer standards.
• The shape of the elastic element used in load cells depends on a number of factors, including the range of force to be measured, dimensional limits, final performance, and production costs.