Load Cells

Load Cells

The heart of any weighing system is the load cell. Load cells are highly accurate trans­ducers which pro­vides the user with informa­tion not generally obtainable by other technology due to commercial fac­tors.Load cells are designed to sense force or weight under a wide range of adverse condi­tions; they are not only the most essen­tial part of an elec­tronic weighing system, but also the most vulnerable. In order to get the most bene­fit from the load cell, the user must have a thor­ough understanding of the technology, con­struction and oper­ation of this unique device. In addition, it is imperative that the user selects the cor­rect load cell for the appli­cation and pro­vide the necessary care for the load cell during its lifetime.

Understanding these important issues and pro­perly maintaining the load cells will ensure trou­ble-free weighing for a long period of time.

Wikipedia states:

A load cell is a transducer that is used to convert a force into electrical signal. This conversion is indirect and happens in two stages. Through a mechanical arrangement, the force being sensed deforms a strain gauge. The strain gauge converts the deformation (strain) to electrical signals. A load cell usually consists of four strain gauges in a Wheatstone bridge configuration. Load cells of one strain gauge (quarter bridge) or two strain gauges (half bridge) are also available. The electrical signal output is typically in the order of a few millivolts and requires amplification by an instrumentation amplifier before it can be used. The output of the transducer is plugged into an algorithm to calculate the force applied to the transducer."