Which excitation voltage should be used

Selection of the right excitation voltage for the strain gauge or sensor

The measuring amplifier ensures the right bridge supply voltage (excitation voltage) For most measuring amplifiers, it is 5V DC.

Please do not confuse the bridge supply voltage with the supply voltage of the measuring amplifier!

The supply voltage of the measuring amplifier is e.g. 24V DC or 12V DC, or 3.7V DC, ... depending on the model.

For the fewest measuring amplifiers, the bridge supply voltage is selectable. 5V are optimal for most sensors and strain gauges.

10V supply voltage can be too much for ultraminiatur sensors with 350 ohms because the heat loss can not be removed.

The drift error by self-heating is usually greater than the gain in signal to noise when the supply voltage is more than 5V.

For strain gauge with 120 ohm resistance and a small measuring grid of e.g. only 1.5mm are 2,5V optimal.

Measuring amplifiers for the voltage analysis are therefore usually working with 2.5V bridge tension.