A load cell is a device that converts the weight (force) of an object into a measurable electrical signal. It is widely used in electronic scales, industrial automation, logistics, warehousing, and other fields. Correct use of load cells is crucial for ensuring measurement accuracy and extending equipment lifespan. The following are the usage methods and precautions for load cells:
Preparation Before Use
Selecting a Suitable Sensor:
Select a sensor with a suitable range based on the weight of the object being measured. It is generally recommended that the working load be between 30% and 70% of the sensor's range to avoid overloading.
Consider the installation environment (such as temperature, humidity, corrosion, vibration, etc.) and select a sensor with a suitable protection rating (such as IP67, IP68) and material.
Select a sensor with a matching structure based on the installation method (cantilever beam, S-type, column type, spoke type, etc.).
Inspecting the Sensor:
Inspect the sensor for damage, deformation, or corrosion.
Confirm that the sensor's terminals or cables are intact.
Prepare Supporting Equipment:
Weighing Instrument (or Transmitter): Used to receive the weak electrical signal (usually mV/V) from the sensor, amplify, process, and display the weight.
Gateway Box (Multi-Sensor System): Used to connect signals from multiple sensors in parallel.
Ensure that the power supply and signal cable specifications of all equipment are compatible.
Installation Method
Installation Location and Foundation:
The mounting surface must be flat, firm, and level, capable of withstanding the load without deformation.
For large weighing platforms (such as truck scales and tank scales), foundation settlement must be uniform; otherwise, it will cause measurement errors or even damage the sensor.
Correct Installation:
Align with the Direction of Force: Ensure the load acts perpendicularly to the sensor's loading surface, avoiding lateral forces, bending moments, or torques. Using spherical washers, spherical bearings, or weighing modules helps with automatic self-alignment.
Tighten Bolts: Use bolts with the specified torque to secure the sensor; overtightening or loosening will affect performance. Note that the bolts should not be subjected to shear force.
Multi-sensor system: Ensure all sensors are installed at the same height, typically using adjustable feet for fine-tuning to ensure even load distribution.
Mechanical limit:
The weighing platform or equipment should be equipped with mechanical limit devices (such as gaps or limit bolts) to prevent overload or impact loads from damaging the sensors.
The limit devices should not contact the weighing platform during normal operation; they should only activate under abnormal conditions.