Measures for noise on the output signal
- Connect the mass of the power supply and the mass of the analog-to-digital converter on the terminal of the measuring amplifier.
"use all lines as a pair to and from the measuring amplifier";
GND on the measuring amplifiers GSV-1 and GSV-11 is then connected twice - The quality of the power supply is decisive for the quality of the output signal.
- The measurement amplifier should have its own power supply,
- A switching power supply can cause noise. If in doubt, better use a linear power supply.
- Insert sensor cables and actuator cables in separate cable channels
- Termination resistance 10kohm or 1kohm on the analog input of the PLC or the AD converter. The electronics of ME measuring systems have 50Ohm output resistance and can therefore be loaded. The error due to load on the output is usually negligible.
- For some AD transducers, it is necessary to carry out an oversampling and subsequent averaging. The noise with AD converters according to the SAR method successive approximation can be quite high ...
- Use pair of twisted lines
- connect the shield only one-sided
Further information can be found in this document: kb-shield.pdf
Over the entire measuring range of force sensors or torque sensors, analog amplifiers usually reach a ratio signal to noise between 1000/1 to 10000/1 (with a bandwidth of 250Hz).