PSU substituted a big ceramic resistor for a capacitor.......why?

Thread Starter

Lumenosity

Joined Mar 1, 2017
614
I have a knock off PSU from a company called VISLONE (formerly NVVV).
It is a 65v 800watt PSU
It is apparently a knock off of a Meanwell 65v 800watt unit (I did not know at the time)

In any event, they replaced one of the capacitors (indicated by the Green Arrow) with a large ceramic resistor and I'd like to know why.
What would happen if I replaced the resistor with the capacitor like the others?

I can give more informatio0n but I'm not sure what additional information would be helpful.
Thank you if you can explain.

By the way.....they sent me a unit that had been seriously damaged and repaired (extremely shoddily) as 'New" (full price)
I didn't find the damage until recently. (see pic 2 below)

Pic 1
NVVV-vs-MeanWell.jpg

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Pic 2 (This is exactly how they sent the "New" PSU to me.) I have since properly repaired all the damaged traces and pads.
VISLONE aka NVVV
20220223_213428[1].jpg
 
Last edited:

DickCappels

Joined Aug 21, 2008
10,186
You said they replaced the (electrolytic?) capacitor with a ceramic capacitor, but did mean that they replaced a capacitor with a resistor as suggested by the title of this thread?

Did you check the component to tell whether it is a resistor or capacitor?

My advice: They did it for a reason and if the power supply is working fine, don't mess with it. The engineers involved probably (but not always : -) understand why they did what they did and you changing it would be blind experimentation, which often results in regrettable results when power circuits are involved.
 

Ya’akov

Joined Jan 27, 2019
9,170
From the photo I can only tell it is not a can like the others but not what it is. Are there markings? Have you measured it?

You said contradictory things:

n any event, they replaced one of the capacitors (indicated by the Green Arrow) with a large ceramic capacitor and I'd like to know why. What would happen if I replaced the resistor with the capacitor like the others?
 

Thread Starter

Lumenosity

Joined Mar 1, 2017
614
From the photo I can only tell it is not a can like the others but not what it is. Are there markings? Have you measured it?

You said contradictory things:
You are right.

I meant large ceramic resistor.

It gets very hot. 175F - 200F
 

Thread Starter

Lumenosity

Joined Mar 1, 2017
614
You said they replaced the (electrolytic?) capacitor with a ceramic capacitor, but did mean that they replaced a capacitor with a resistor as suggested by the title of this thread?

Did you check the component to tell whether it is a resistor or capacitor?

My advice: They did it for a reason and if the power supply is working fine, don't mess with it. The engineers involved probably (but not always : -) understand why they did what they did and you changing it would be blind experimentation, which often results in regrettable results when power circuits are involved.
It is a ceramic resistor.
The company is somewhat fly-by-night (as indicated by their attempt to copy Meanwell and use a logo that could be easily confused with Meanwell.)

Also, looking at the horrendous mess they made on the bottom of the board and shipped the unit as new speaks for itself.
(Please see photo of their ??? repair ??? of the board at the bottom of post #1 which I purchased as brand new.)
Which leads to this thread. I think they would do almost anything, even if it was inappropriate or dangerous.

That's mainly why I asked.

Hope that makes it clearer.
 
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