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DC Load - I need some guidance
mvno_subscriber:
--- Quote from: 2N3055 on June 14, 2024, 07:41:00 am ---That whine is either coming from PWM for fan or from a switcher PSU. If it is there it won't get tired and go somewhere else....
--- End quote ---
Is there anything I can do to dampen it without meddling with its insides? Could it be its placement somehow acoustically amplifies the sound? I find it difficult to imagine that this is how it's supposed to be.
2N3055:
--- Quote from: mvno_subscriber on June 14, 2024, 07:56:46 am ---
--- Quote from: 2N3055 on June 14, 2024, 07:41:00 am ---That whine is either coming from PWM for fan or from a switcher PSU. If it is there it won't get tired and go somewhere else....
--- End quote ---
Is there anything I can do to dampen it without meddling with its insides? Could it be its placement somehow acoustically amplifies the sound? I find it difficult to imagine that this is how it's supposed to be.
--- End quote ---
I don't know. First you need to realize where is comes from.
If it comes from fan PWM, you have actual fan being a speaker....
It might change as fan RPM change.
If it comes from PSU, then it is some component that is making a noise. A inductor, transformer or something else magnetostrictive or piezoelectric (like ceramic capacitors for instance)..
It might as well be a standard thing on these.
mvno_subscriber:
--- Quote from: 2N3055 on June 14, 2024, 08:10:16 am ---
I don't know. First you need to realize where is comes from.
If it comes from fan PWM, you have actual fan being a speaker....
It might change as fan RPM change.
If it comes from PSU, then it is some component that is making a noise. A inductor, transformer or something else magnetostrictive or piezoelectric (like ceramic capacitors for instance)..
It might as well be a standard thing on these.
--- End quote ---
Tried loading it with 150W to make the fans spin up, and spin up they did. Still the same whining, though. Had ringing in my ears 15 minutes after I turned it off. I'll call for a replacement unit on monday, this has to be defective. Right now it's a health hazard.
That said, I really like it so far and I don't want to let it go. It has already gotten a place in my heart! Let's hope a new unit will fix things.
Martin72:
--- Quote ---If it comes from PSU, then it is some component that is making a noise. A inductor, transformer or something else magnetostrictive or piezoelectric (like ceramic capacitors for instance)..
--- End quote ---
These are usually inductors such as core chokes or transformers.
The wire windings are relatively loose around the core and start to vibrate when current flows, this is transferred to the core and the whole thing forms a small "loudspeaker".
We impregnate our coils/transformers under vacuum, which reduces the vibrations enormously.
What you can do "privately" and afterwards is to localize the sounding component and cover it with e.g. silicone.
2N3055:
--- Quote from: Martin72 on June 15, 2024, 10:44:17 pm ---
--- Quote ---If it comes from PSU, then it is some component that is making a noise. A inductor, transformer or something else magnetostrictive or piezoelectric (like ceramic capacitors for instance)..
--- End quote ---
These are usually inductors such as core chokes or transformers.
The wire windings are relatively loose around the core and start to vibrate when current flows, this is transferred to the core and the whole thing forms a small "loudspeaker".
We impregnate our coils/transformers under vacuum, which reduces the vibrations enormously.
What you can do "privately" and afterwards is to localize the sounding component and cover it with e.g. silicone.
--- End quote ---
I also have heard elkos and ceramic capacitors "sing" quite nicely...
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