Interface Load cell With 8051

Load cell is a passive transducer or sensor which converts applied force into electrical signals.

  • They are also referred to as Load transducers.
  • There are many varieties of load cells, strain gauge based load cells are the most commonly used type.
  • Load cells use different operating principles.
  • 1.Load Cells based on fluid pressure.
  • 2.Load Cells based on elasticity.
  • 3.Load Cells based on magnetostriction effect or piezoelectric effect.
  • Load cell primarily consists of a spring material and strain gauge.
  • Spring material causes strain due to applied load and strain gauge changes its resistance in accordance with the change in strain.
  • A mechanical arrangement, the force being sensed deforms a strain gauge.
  • The strain gauge measures the strain as an electrical signal.
  • 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 can be scaled to calculate the force applied to the transducer.


  • Weight Machine.

Hardware Required

  • Load Cell.
  • ADC 0804.
  • Instrumentation Amplifier.
  • 8051 MicroController.