Understanding the Different Types of Load Cells
Load cells are very important to understand for a number of reasons. If you’ve never heard the words “loadcell”, it can be a lot to understand at first. Essentially, load cells are used to measure the force that is exerted on certain objects. These objects could range from bridges to large buildings to overpasses, and measuring the force on these objects is very important.
So what are the different types of load cells, and what do they do? There are three main different types of load cells, all of which perform various functions. If you’re looking to get a better understanding of the different types of load cells so you can better know what it is they do, check out this article for detailed explanation on the different types of load cells.
Before understanding the different types of load cells, you must first understand how those load cells are used. For most load cells, an industrial amplifier is used in order to perform precision based summing on a multiple of load cell signals in order to weigh applications.
Hydraulic Load Cell
For a hydraulic load cell, the piston is placed into a very thin elastic diaphragm, and doesn’t come in contact with the load cell at all. There are steps in place that are designed to prevent the diaphragm being strained if the loads of the cell surpass the stated limit.
With the hydraulic load cell, the cell is filled with oil. When that load is then applied onto the piston, the piston’s movement combined with the way that the diaphragm is arranged means that the oil pressure will be increased. When the oil pressure is increased, there is a change in pressure on the tube that’s connected with the cells.
Pneumatic Load Cell
Pneumatic load cells are different than hydraulic load cells in that the load cell is manufactured so that it regulates the balancing pressure automatically. The air pressure is then applied to only one side of the diaphragm, and then the air leaves through the nozzle that’s on the bottom of the load cell.
Attached to the pneumatic load cell is a pressure gauge in order to measure the pressure inside of the cell. The diaphragm is deflected, which in turn changes the airflow that goes through the nozzle, and ultimately it changes the pressure that’s in the chamber.
Strain Gauge Load Cell
A strain gauge load cell is a longer conductor which is arranged in a sort of zigzag type pattern. As the load cell is stretched, its resistance increases. When the load cell is bent downward, the gauges on the top of the load cell are stretched while they gauges on the bottom of the load cell are compressed.
While those are the three main types of load cells, there are also different, lesser known and used types of load cells. These include piezoelectric load cells and vibrating wire load cells, both of which are used in a variety of different settings.
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