This is related to field wiring schemes and interference. Sometimes tens of transducers are needed to be coupled to a single-ended data acquisition board's analog input channels where the transducers are powered from a single power supply. For instance the two modules(it could be transducers) below are powered from one 5V power supply. And in this case as you see(upper left screw terminals) each modules are wired separately at their power terminals from the power supply.

enter image description here

Here below is a closer view where power terminals and the signal outputs to a DAQ is shown(Upper left two screw terminals on the modules are for power and upper right two screw terminals are for signal output coupled to the DAQ channels):

enter image description here

To make the question question more clear I draw the following different schemes:

enter image description here (left-click to enlarge)

Tr0, Tr1, Tr2 are transducers, PSU is the power supply.

Currently the uploaded photos I guess show the Figure3 wiring configuration. In Figure1, +power terminals and the power grounds is daisy chained. In Figure2, only the +power terminals are daisy chained and the grounds are star connected.

(The signal ground and the power ground is connected on the back panel even though inside the module they are isolated.)

Which scheme would be more immune to interference and noise?

  • \$\begingroup\$ Fig 3 is best followed by Fig 2 then 1. But in order of increasing hassle to wire up it is reversed. \$\endgroup\$ – DKNguyen Apr 12 at 14:05

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.