i was considering my measurement system's ground to be isolated from my simulated RTD (DPMs) system. Then just as an experiment, i made both systems ground common, noise got removed nd i was happy at the end of the day but i was shocked by this coz DPM ws only acting as a variable resistor nd i didnt need to do thz for simple Pots. Well, i think its just because of the active nature of DPM as compared to passiveness of simple variable resistor. i don't think there could be any other justification for thz, what 'd u say??