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When building a custom case for a computer that will be mounted on the wall, hanging, suspended are there any special considerations for the PSU or grounding?
Assumption 1 – I assume the MB will need to make contact with the metal case and using brass standoffs are fine. Because the custom 'wall case' is mostly metal (20×20 extrusions), those standoffs can safely be mounted to the metal case, making metal-contact with the MB as one would in a normal case.
OR – In this situation should Nylon standoffs be used instead to insulate the MB from the frame? (Why do I think this: because of interference, RF, avoid making the computer into an antenna, etc.)
Assumption 2 – I assume the PSU will need to make grounded metal-to-metal contact with the case as well just like a normal build.
OR – In this situation should washers or nylon be used to insulate the PSU from the case since it's wall mounted? (Why do I think this: because of RF and to avoid static problems or making an electromagnet.)
Clear acrylic will be used for a MB bracket and a PSU bracket (to make it easier to secure those components to the 20×20 metal extrusion frame), which brings up the following considerations:
If those custom acrylic mounting brackets will insulate the PSU from the metal case, then is additional grounding is needed to ground the PSU to the case?
If those custom acrylic mounting brackets will insulate the Motherboard from the metal case, then is additional grounding is needed to ground the Motherboard to the case?
Neither the MB nor the PSU needs to be grounded to the case, ergo: mounting them to acrylic frames with no metal contact or additional grounding is fine.
Conclusion A: None of the above matter? I.e., ground or no ground, a high quality PSU and good MB will be fine mounted in a wall case because the wiring is grounded through the PSU->Plug->Outlet->Home wiring – therefore, no special considerations are needed. RF interference, static and electromagnetism will not be a problem for a suspended wall mounted computer system and each component can be insulated from the others with nylon standoffs, acrylic brackets, insulating washers; even the frame itself could be plastic or acrylic.
Conclusion B: All of the above matter? I.e., following the path of the ground from the power outlet through the computer system => the PSU, the MB and the case should all be connected and grounded, a metal frame is a good idea, metal mounting plates are better than acrylic and nylon should be avoided.
Let us assume in all cases here that the unit is "floating in space" (connected only by the PSU power cord) and the wall itself may be glass, metal, wood, rubber or simply "air" if the unit is hung from wires. Let us also assume that audio speakers will be connected and that Wi-Fi, cellphones and radios may be in use near the unit.
In closing: Which of these conclusions is true (A or B), and which, if any, of my assumptions (1 & 2) is incorrect?
Because this was "closed" lets make the 4 questions "more clear" for the admins here... I am asking "how to properly ground the PSU and the Motherboard on a WALL HANGING custom computer.
There are 4 simple questions:
- Do I need to ground the Motherboard to the case using metal screws?
- Do I need to ground the PSU using metal screws?
- Can I use Nylon on the Motherboard Risers?
- Can I use Nylon on the PSU bracket?
2As I was adding an answer, the question was closed. Conclusion A is the answer. Basically all of the grounding is done through the cable from the main power supply cable between motherboard and PSU via the 24 pin connector. The PSU is then grounded through the AC power cord to the ground lug on your outlet. – DrZoo – 2019-12-02T21:47:38.950
The PSU is grounded through the power cord, makes no difference if it is wall mounted. Do not insulate it from the case. – Moab – 2019-12-02T22:30:45.363
BTW, are you just fastening a computer to the wall, or fastening the internal components to a non-metal enclosure you are making? It doesn't make any difference what it sits on or hangs from; it's self-contained. But if you are creating your own case, you need to be concerned with things like internal grounds and shielding, your neighbors complaining that you are interfering with their TV reception, and cooling and heat dissipation. The case isn't just a box to hold the parts. – fixer1234 – 2019-12-03T16:15:23.537
– DrZoo - thank you. I can tell Ramhound, harrymc, DavidPostill (who flagged the question) were not familiar with linear logic and "drawing conclusions" using scientific methodology. You deserve credit for the answer. Know any way to get this "unflagged"? it should not be closed. – Christian Žagarskas – 2019-12-03T21:23:48.913
@ChristianŽagarskas Electricity will always take the path of least resistance, which is why it's recommended to have all PCB components with a chassis ground grounded to the internal chassis via metal screws. The main purposes of the chassis ground are to prevent ground loops, noise from EMF, and external ESD from damaging the multiple PCB boards within a PC (MB, components, HDDs, etc.)... this is also why externally grounded anti-ESD wrist straps are used when working on PCB components. Before deciding whether to chassis ground the MB and components, please do a bit of research on google. – JW0914 – 2019-12-04T11:02:48.993
@fixer1234 Yes, it can be suspended in several ways, wall mount, ceiling mount with cables. AND yes we have discovered some surprises with RF interference and even cell phone's some of which I was able to solve with ferrite core cable shields, which is what brought me here... figured I would ask "hey, anyone built a wall hanging computer with a custom non-metal case?" because its not like the normal average custom build, there are some surprises... – Christian Žagarskas – 2019-12-05T19:57:10.367