Replacing Capacitors in power supply unit question

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khoadk2193

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Replacing Capacitors in power supply unit question
« on: 14 Nov 2017, 03:49 am »
Hi guys,
I’m on a project of restoring my Denon dcd 3520 cd player and so far i replaced all the electrolytic caps on both boards of it and it works really well with alot of improvements. Then i move on with the 2 big caps in the power supply unit with 4700uf at 50v. I looked up online and found some of them with same values but they’re pretty small compare to the original one. I read online that i should replace for those that have the same dimension and i can bumb up the capacitance with no issues. Is it true that i can do that?

Kevin

jules

Re: Replacing Capacitors in power supply unit question
« Reply #1 on: 14 Nov 2017, 05:37 am »
Quality, capacitance and voltage rating matter, dimensional size doesn't, so if you're really keen you could go for something like Mundorfs as a replacement though being more moderate Nichicon KG gold are a perfectly good power supply cap. You could probably go up to 6,800uF though it might not make a significant difference. Don't take the capacitance up too high though.

You could add a smaller 1/100th or even 1/1000th cap in parallel with the larger pair. The logic behind this is that even the power supply caps are part of a circuit and the smaller cap will allow higher frequencies to pass through the circuit where the larger caps might be falling away a bit.

khoadk2193

  • Jr. Member
  • Posts: 5
Re: Replacing Capacitors in power supply unit question
« Reply #2 on: 14 Nov 2017, 07:07 am »
Thank you for your detailed reply jules. So if i put 6800 in there, is it gonna harm other components?

richidoo

Re: Replacing Capacitors in power supply unit question
« Reply #3 on: 14 Nov 2017, 12:47 pm »
Thank you for your detailed reply jules. So if i put 6800 in there, is it gonna harm other components?

No harm increasing to 6800uF, but 4700 is all you need, says Denon engineers. Make sure it's same or higher voltage and temperature ratings. Size does not matter, as long as it will fit. Make sure the distance between the leads is the same as the old caps so they will fit flat against the PCB.

Speedskater

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  • Kevin
Re: Replacing Capacitors in power supply unit question
« Reply #4 on: 15 Nov 2017, 05:00 pm »
Newer electrolytic caps tend to be smaller than older ones.
When replacing the caps make sure that:
a] the value is the same or larger. (a little larger is good, but way larger can cause problems)
b] the voltage rating is the same or larger.
c] the temperature rating is the same or higher.
d] the mounting is compatible.

Adding small caps in parallel is a waste of time. ( the small caps are already just where they need to be and it's not at the electrolytics.