Tuesday 18 April 2017

switch mode power supply - Are the ground wires and the earth creating a loop in this system?


Below in the photo both SMPS power supplies powers some DAQ boards. I named them as 12V PSU1 and 5V PSU2. As you see the PSU1 and PSU2 are daisy chained at their mains entry(line, neutral, earth):



enter image description here


And here is the basic diagram:


enter image description here


Above both power supplies powers the different parts of the remote device Device 1. In real there are six of them but or simplicity I draw one device. The PSU1 directly powers the device, the PSU2 powers the 5V part of the device through a USB Hub.


I named the nodes as A, B, C, D and E.


Knowing that in SMPS A E and C D nodes are capacitively coupled, is there a loop for high frequency across A B C D and E?


If there is can I eliminate that by cutting the daisy chain earth between D and E?


Edit:


Block diagrams of the power supplies:


enter image description here



enter image description here


And here is the power line filter.




No comments:

Post a Comment

arduino - Can I use TI's cc2541 BLE as micro controller to perform operations/ processing instead of ATmega328P AU to save cost?

I am using arduino pro mini (which contains Atmega328p AU ) along with cc2541(HM-10) to process and transfer data over BLE to smartphone. I...