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SensorsBasicload cellstrain gaugeWheatstoneHX711ADCcalibrationtare

Load cell

In 30 secondsStrain gauges glued to a piece of metal change their resistance slightly when it bends. A Wheatstone bridge gives a few millivolts, an ADC turns them into counts and calibration converts those to grams.

Also available in: Català · Castellano

The chain behind every sensor

Quantity → transducer → electrical signal → ADC → number (counts) → calibration → units. When something measures wrong, find which link is failing.

How it works

  • A strain gauge is a very fine wire glued to a metal part; when the part bends, its resistance changes very slightly.
  • Four gauges in a Wheatstone bridge give a few millivolts (typically 1 to 3 mV per volt of excitation; with 5 V, about 10 mV at full scale).
  • A 24-bit amplifier-ADC (HX711) turns that into counts.

Tare and calibration

  • Tare: set zero with the scale empty.
  • Calibration: place a known mass to find out how many counts make a gram.
  • Averaging: less noise, but a slower response.

In the demo

Add a load and follow the chain: weight, strain, resistance, mV, counts. Tare, calibrate and raise the averaging.

Common questions

Does it measure mass or force? Force (strain). It is calibrated with a known mass to get grams, assuming local gravity.

Interactive demo

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