What are the Components and Functions of a Weighbridge?

In order to be able to measure the weight of the truck while it is running, a truck weighbridge is also called a truck scale, which is a system composed of several components that work together.

Five Main Components of Weighbridge Truck Scale

Concrete foundation. Ensure that it is a basic permanent facility.

Steel platform. This is the structure that creates the driving surface for the truck.

Weighing sensor. It is a key component of using a weighbridge truck scale to measure weight. It is a sensor that converts force into a measurable electrical output.

Terminals. Sometimes called an indicator, the terminal is a control panel scale.

Cable. The signal from the weighbridge load cell must be transmitted to the terminal input. In most cases, this is done via a cable.

Working Process of the Truck Scale

First of all, we must understand a common sense, that is, what the weight of the payload means. The weight of the payload, including the weight of the truck, is measured by first driving the truck onto the weighbridge.  This weight is referred to as the gross weight. To obtain the weight of the payload, then the tare weight must be subtracted from the gross weight, which is the weight of the empty car.

Install the entire steel platform on the load cell. Each load cell is composed of durable materials. Commonly used durable materials are steel and concrete, on which one or more strain gauges are connected or embedded. The strain gauge consists of one or several wires that transmit a weak current. When the sensor bears weight, the wire in the strain gauge of the load cell changes slightly. The change in the wire causes the resistance of the current passing through the wire to be different.

The analog signal from each load cell is sent to the junction box with the combination of multiple load cells, and then the summed signal is transmitted to the weighbridge controller. The analog-to-digital converter is used to convert from the wiring. The signal of the box is digitized, and the weighing is recorded on the LED display. Most of the floor scales are operated in this way. Based on this, we have developed many types of floor scales, such as sartorius weighbridge, computerized weighbridge, dharam kanta weighbridge, etc.

Calibration Test Method for Weighbridge

Perform a zero-calibration test. The empty weighbridge platform has been tared and calibrated to zero.

Perform a range test. It is very important to calibrate the weighbridge like heavy duty weighbridge and mettron weighbridge with the known maximum weight. The general rule of thumb for calibrating any weighbridge system is 10% of its total capacity. For example, a 10-ton reference standard test weight can be used to calibrate a 100-ton floor scale.

By ensuring that the same weight is always displayed when a given calibration load is applied in any direction, a repeatability test is required to ensure the repeatability of the weighbridge system.

Carry out load cell eccentricity test. The counterweight unit in the weighbridge may produce unequal output, resulting in a rotation angle error each time the weighing is performed. The general rule of thumb for eccentricity test is to test each load cell with the total load of the weighbridge. For example, a floor scale with a capacity of 60 tons (with 6 load cells) can be tested on each load cell (with a weight of 10 tons).