This full bridge strain gauge measures stress, force, or weight. It works by sensing tiny bends or changes in a surface. The full bridge setup has four active parts. This gives it more sensitivity and temperature balancing than quarter or half bridge setups. Features and Benefits
- Full Bridge Setup - It gives a stronger signal and better accuracy for precise measurements.
- Foil Design - The foil construction lets it fit onto surfaces. It also provides a steady base for the resistive grid.
- Two Resistance Choices - It comes in BF350 (350 ohm) and BF1K (1000 ohm) versions to fit different circuit designs.
- Main Sensing Part - This is the basic piece you need to build your own custom load cells or pressure sensors. Applications
- Making a custom digital scale for weighing items with high accuracy.
- Adding sensors to mechanical parts to watch stress and fatigue as they happen.
- Building a system to monitor a structure's health and detect strain in beams or supports.
How It Works
A strain gauge is a sensor that measures strain. This product is a Full-Bridge Strain Gauge, a type of precision foil sensor. When an object is subjected to an external force, it deforms, either stretching or compressing. This deformation is known as strain. Strain gauges work by converting this mechanical deformation into an electrical signal. As the object strains, the resistance of the gauge changes proportionally. This change in resistance can then be measured to determine the amount of strain.
Measuring the Output
The Full-Bridge Strain Gauge, with its 350 Ohm resistance, is designed for precise measurement. Due to its full-bridge configuration, it offers enhanced sensitivity and stability compared to other gauge types. The change in electrical resistance across the gauge is typically very small. To measure this accurately, the gauge is usually connected to a Wheatstone bridge circuit. This circuit converts the resistance change into a measurable voltage output. This voltage is proportional to the applied strain, allowing for precise quantification.
Common Applications
Strain gauges are widely used in various applications where precise measurement of force, weight, and pressure is required. This Full-Bridge Strain Gauge is suitable for general-purpose strain measurement. Common applications include:
- Structural health monitoring
- Material testing
- Load cells for weighing systems
- Transducers for pressure and torque measurement
- Industrial automation
How They Work
Strain gauges, including this precision foil sensor, operate on the principle of piezoresistivity. When the object to which the gauge is mounted deforms, the thin metallic foil within the gauge also deforms. This deformation causes a change in the electrical resistance of the foil. Stretching the foil increases its length and decreases its cross-sectional area, leading to an increase in resistance. Compressing it has the opposite effect. This change in resistance is directly proportional to the strain applied to the object.
Measuring the Signal
The electrical signal from a strain gauge, such as this Full-Bridge Strain Gauge, is typically a small change in resistance. To effectively measure this, the gauge is integrated into a Wheatstone bridge circuit. This circuit consists of four resistors, with the strain gauge forming one or more arms of the bridge. As the gauge's resistance changes due to strain, the balance of the bridge is upset, producing a measurable voltage output. This voltage signal can then be amplified and processed by data acquisition systems to display the strain value.
Gauge Type: Full Bridge. Mounting Type: SMD. Product Type: Strain Gauge. Quantity: 10 pieces. Base Material: Phenolic resin or similar polymer film. Grid Material: Constantan foil. Operating Temperature Range: -30°C to +80°C. Application: Pressure sensors, load cells, structural testing, computer applications. Bridge Configuration: Full Bridge. Fatigue Life: 10^6 cycles at ±1500 µε. Gauge Factor: 2.0 to 2.2 (typical). Gauge Resistance (BF1K-3EB): 1000 Ω ±0.2%. Gauge Resistance (BF350-3EB): 350 Ω ±0.2%. Model Numbers: BF1K-3EB, BF350-3EB. Package Type: SMD (Surface Mount Device). Precision: High Precision. Product Name: Full Bridge Strain Gauge. Quantity: 10 pieces. Sensor Type: Strain Gauge. Strain Limit: 2% to 5% (typical). Q: What do the BF350 and BF1K part numbers mean? A: The number indicates the sensor's nominal electrical resistance. The BF350-3EB has a 350 Ohm resistance, while the BF1K-3EB has a 1000 Ohm (1kΩ) resistance. You should choose the one that matches the design of your amplifier circuit.. Q: What is the correct way to attach this to a surface to get an accurate reading? A: For best results, you must clean the target surface completely. Then, use a dedicated strain gauge adhesive to bond the foil, applying firm and even pressure to remove any air gaps between the sensor and the surface.. Q: Can I connect this strain gauge directly to my microcontroller's analog input? A: No, the change in resistance from strain is extremely small and can't be read by a standard analog-to-digital converter. You'll need a specialized amplifier circuit, like a module using the HX711 chip, to boost the signal to a measurable level.. Q: Are these gauges reusable? What if I mess up the installation? A: These are very delicate and are considered consumable items, so they are not reusable once the adhesive is applied. Damage during installation is not covered, so we suggest ordering a few extras if this is your first time working with them.. Q: Why should I use a full-bridge strain gauge like this instead of a single-element one? A: This full-bridge strain gauge has four sensing elements arranged in a Wheatstone bridge configuration. This setup is inherently more sensitive to strain and also provides automatic temperature compensation, which results in a more stable and precise measurement..