An important parameter of the load cell is its sensitivity. Most sensors have a standard sensitivity, such as 2mV/V at the rated load, that is, the sensor at the rated load bridge output a voltage signal proportional to the supply voltage of 2mV/V.
For example, a weighing rated load is 100kg, the sensitivity is 2mV/V, the sensor is connected to the instrument, the excitation voltage (supply voltage) of the instrument is 10V, then load 100kg weights on the sensor, The output of the sensor is 100kg weight /100kg rated X 2mV/V sensitivity X 10V excitation voltage =20mV output voltage. If there is no weight on the sensor (including the scale table above the sensor), then the output of the sensor is 0mV.
Dial the digital multimeter to 200mV file, the pen to test the sensor signal at both ends, load heavy objects on the sensor, if the sensor signal rises, the number of the instrument changes, indicating that the sensor is good, if there is no item on the sensor, and the measured signal voltage is far beyond the zero point, such as 10mV, indicating that the sensor has been damaged.
In fact, the voltage signal measurement method is the correct measurement method of the sensor, but the accuracy of the mv(millivolt) measurement file of our ordinary digital multimeter is limited, only 200mV, and some tables do not even have mv this gear, and the signal is very small, vulnerable to interference and other reasons. Therefore, when measuring, S+ and S - should be interrupted from the instrument in the measurement, and be careful about the impact of various factors on the signal, so as not to cause misjudgment.
For large load load load sensors with this method is a bit of a drop in the bucket, a rated load of tens of tons of sensors in the absence of other tools can not be carried out output signal testing.
