Common Types of Load Cell: A Comprehensive Guide
What is a Load Cell?
A load cell is a transducer that converts force or weight into an electrical signal. It is commonly used in industrial settings to measure and monitor the force applied to various objects and systems.
How Load Cells Work
Load cells operate on the principle of strain gauge technology. When a force is applied to the load cell, it deforms slightly, causing a change in electrical resistance. This change in resistance leads to the generation of an electrical signal, typically in the form of voltage or current, or sometimes both. This signal is then transmitted to an indicator or data acquisition system for interpretation. The indicator processes the signal and provides a reading corresponding to the applied force. Calibration of the indicator is crucial to ensure accurate measurements and may involve adjusting the sensitivity and offset to match known force values.
Compression Load Cells
Compression load cells are specifically designed to measure compressive forces, making them ideal for applications involving high load situations such as uniaxial pressing.
How Compression Load Cells Work
Compression load cells typically consist of a metal body with strain gauges attached. When a force is applied to the load cell, it causes the metal body to deform slightly, which in turn changes the resistance of the strain gauges.
Compression load cells come in several types, including button type, pancake, pass through (with a hole in the middle a.k.a. doughnut), low profile, miniature. Some compression load cells are designed for use with ball bearings to make sure the weight is evenly distributed and acts perpendicular to the load cell.
We have a range of low profile button type which are ideally suited to high load pressing. In uniaxial pressing like is common for our die sets (pressing in 1 axis) we know the force is coming vertically with little or no lateral forces, so we have designed out load cells with flat pressing surfaces all and can be placed directly below (or above) your pellet die set. We also sell with the calibrated indicator so you can use straight out of the box.
Advantages:
- High accuracy
- Compact
- Suitable for high load applications
- Durable and long-lasting
Disadvantages and Limitations:
- Can be sensitive to temperature changes
- May not be suitable for applications with lateral forces
Common Uses:
- Uniaxial pressing
- Hydraulic presses
- Material testing
See a fuller description of compression load cells here.
Micro Load Cells
Also known and low profile, mini load cells or button load cells - Micro load cells are a subset of Compression load cells. We give them a separate section here as they are just so handy!
Micro load cells, as their name suggests, are compact compression load cells designed for precision measurement in small-scale applications. These miniature load cells offer accurate force measurement while maintaining a small footprint, making them ideal for situations where space is limited. Typically used in conjunction with portable force readers, micro load cells provide reliable readings for forces ranging from 10 to 2000 kg. Despite their diminutive size, micro load cells boast impressive accuracy, ensuring precise measurements in various pressing applications such as small pellet press die sets. Whether used in manual presses, vices, or arbor presses, micro load cells deliver consistent and dependable results, making them indispensable tools in industries where precision is paramount.
Tension Load Cells
Tension load cells are designed to measure the pulling force or tension applied to an object. They typically consist of a load-sensitive element connected to an external support structure.
How Tension Load Cells Work
When a force is applied to the load cell, it causes the load-sensitive element to stretch or elongate, resulting in a change in electrical resistance. This change is then converted into an electrical signal proportional to the applied tension.
Advantages:
- Accurate measurement of tension forces
- Can be used in both static and dynamic applications
- Wide range of capacities available
Disadvantages and Limitations:
- May be affected by temperature variations
- Installation may require careful alignment
- Not suitable for compression applications
Common Uses:
- Crane scales
- Tensile testing
- Force measurement in conveyor systems
See a fuller description of tension load cells here or buy tension load cells here.
Beam Load Cells
Beam load cells are commonly used in industrial weighing and force measurement applications. They are designed to measure loads applied perpendicular to the beam axis.
How Beam Load Cells Work
Beam load cells typically consist of a metal beam with strain gauges bonded to the surface. When a force is applied perpendicular to the beam, it causes the beam to bend slightly, resulting in a change in electrical resistance in the strain gauges.
Advantages:
- High accuracy
- Can accommodate large loads
- Insensitive to side loads
Disadvantages and Limitations:
- May require additional mounting hardware
- Not suitable for dynamic or high-speed applications
- May be affected by temperature variations
Common Uses:
- Industrial weighing scales
- Material handling systems
- Tank and hopper weighing
See a fuller description of beam load cells here.
Planar Load Cells
Planar load cells, also known as platform load cells, are designed to measure forces applied over a large surface area. They are commonly used in applications where precise force measurement is required.
How Planar Load Cells Work
Planar load cells typically consist of a flat, plate-like structure with strain gauges bonded to the surface. When a force is applied to the load cell, it causes the plate to deform slightly, resulting in a change in electrical resistance in the strain gauges.
Advantages:
- High accuracy over a large surface area
- Can accommodate uneven loads
- Insensitive to side loads
Disadvantages and Limitations:
- May be affected by temperature variations
- May require additional support or reinforcement for large loads
- Not suitable for high-speed applications
Common Uses:
- Vehicle weighing systems
- Industrial platform scales
- Material testing applications
See a fuller description of planar load cells here.
Single Point Load Cells
Single point load cells are designed for applications where the load may be applied off-center or in multiple directions. They are commonly used in retail and industrial weighing applications.
How Single Point Load Cells Work
Single point load cells typically consist of a load-sensitive element mounted on a single support point. When a force is applied to the load cell, it causes the load-sensitive element to deform slightly, resulting in a change in electrical resistance.
Advantages:
- Accurate measurement of off-center loads
- Compact design
- Easy to install and integrate into existing systems
Disadvantages and Limitations:
- May be sensitive to side loads
- May require additional support for large loads
- May be affected by temperature variations
Common Uses:
- Retail scales
- Counting scales
- Checkweighers
See a fuller description of single point load cells here.