Inputs of a W525 could be perturbed from an other input?

FAQ #102007

Module PCD2/3.W525 are not designed as other analog input modules (as PCD2/3.W340 or W200 for example). Particularities of the module W525 are the following:

-        Galvanic separation of inputs/outputs.

-        Differential inputs/outputs.

For most of sensors, which are used in differential mode, no problem could be detected from other inputs.

With the use of non-differential sensor, when all (-) parts would be connected together, perturbation might be visible on another channel. As the W525 module has galvanic isolation and due to the design of the module, unwanted return current could appear and disturb other inputs.

If you experience such situation, there is a possibility to connect the (-) of your sensor to the gnd of the module. By doing it this, galvanic isolation of the whole module will not be valid anymore.

Therefore is a special configuration of the jumper possible.