How a Strain Gauge Based Load Cell Measures Force

Strain gauge load cells are critical for accurate force and load measurement in both geotechnical and structural applications. They deliver precise and repeatable data across multiple sectors and applications:

• Mining

• Infrastructure

• Bridge structures

• Verifying bearing loads

• Other uses

In this article, we explain how strain gauge load cells work, how they provide such accurate data and how Monitel consultants use their local knowledge to ensure maximum sensor performance across Western Australia. For more information or to discuss your site, get in touch.

What Is a Strain Gauge Load Cell?

A strain gauge load cell is a sensor that converts mechanical force into an electrical signal using a strain sensitive material that deforms under an applied load. Attached to that material is one or more gauges that change resistance as they are stretched or compressed. That change is representative of deformation, which is proportional to the applied load.

The electrical signal is measurable, can be logged in most standard data systems and is used to interpret how much force is being applied to a structure.

The Wheatstone Bridge

A Wheatstone bridge circuit is what converts resistance changes into a readable output. It improves sensor sensitivity and can detect millivolt range signal variations. Monitel typically employs one of two setups:

• Full bridge configurations using four strain gauges, increasing output sensitivity and improving temperature compensation.

• Half or quarter bridge arrangements in simpler or constrained installations

Our consultants select a bridge configuration that aligns with the measurement range, environmental constraints and your monitoring goals.

Factors That Influence Data Accuracy

The accuracy of a strain gauge load cell’s performance is dictated by a host of internal and external factors. These include:

Material and Geometry of the Sensing Element

The mechanical body of the cell is designed to deform within a predictable and, importantly, uniform way. Most units are made from either steel or aluminium and selecting the right material is critical in resisting corrosion, fatigue and creep over time. Monitel consultants can assist you with sensor selection.

Strain Gauge Placement

Gauges are placed at points of maximum strain on the cell body. Poor attachment will limit the accuracy of your monitoring, whether it be through misalignment or uneven bonding. Our team works closely with suppliers to ensure gauge placement is tailored to each installation.

Calibration

A load cell must be calibrated against known forces to record linear data. Monitel ensures the calibration process accounts for manufacturing variances and geotechnical realities.

Temperature Compensation

Strain gauges are prone to thermal expansion, which, left unaddressed, can alter readings. Most units have an inbuilt temperature compensation gauge but, if not, our consultants will pair a suitable tool that factors changes into your data interpretation.

Signal Amplification and Shielding

Signal condition is essential to accurate load cell data. Monitel installs amplifiers close to the unit to minimise noise over long cable runs and properly shields wiring from electrical interference.

How Monitel Maximises Accuracy in the Field

Our consultants have vast experience completing precision monitoring on some of Western Australia’s harshest, most remote sites. To ensure accuracy in extreme temperatures and dynamic environments, we use:

• Rugged Housing: Sensors are corrosion resistant, have ingress protection and are maximised for long term stability

• Pre-Installation Testing: All units are tested prior to deployment to confirm calibration and signal integrity

• Integrated Data Acquisition: Sensors are connected to your telemetry and logging systems for remote access and automated recording

The Monitel approach is designed to ensure that data is accurate, consistent and easily interpreted by site managers.

Our Experience

There are countless sites across Western Australia suited to the application of a strain gauge load cell. Monitel’s deployment experience includes:

• Measuring load transfer in anchored retaining walls

• Long term monitoring of bearing load distribution in bridges

• Verifying pre-loads and redistribution during excavation and construction

• Measuring loads in cable bolts and rings in shaft infrastructure

These sensors are also valuable in short term setups.

Enquire Today and Arrange Strain Gauge Load Cell Monitoring with Monitel

Strain gauge load cells are one of the most efficient and reliable ways of measuring force in structural and geotechnical systems. But, critical to their accuracy is proper design, installation, calibration and maintenance.

Monitel combines market leading technology with system design skills backed by years of local experience. Our consultants have aided sites across Western Australia in achieving reliable, precise data that supports long term compliance and confidence.

For more information on the availability and price of strain gauge load cells and other sensors, contact our team.