FIC VA-503+ best replacement for Vcore caps

[mzolli]

Re: FIC VA-503+ best replacement for Vcore caps

Hi all,

I stumbled onto this thread and am dealing with a VA-503+ recap, myself. I went onto mouser.com / digikey.com to find suitable caps and realized I needed the ESR. To that end, I recently discovered / bought an LCR-T4 Mega328 which seems to do reasonably well with ESR measurements.

Long story short, I popped off the caps from the board that looked good and measured them as follows. (Please note: these are my measurements of capacitors which are old, unknown whether the caps are completely out of spec & unknown whether my measurement device is accurate. In other words, caveat emptor!)

Farads  Voltage    ESR    VLoss
1500uF   6.3V     0.34Ω   4.4%
1000uF   10V     0.37Ω   2.9%
10uF    25V     6.2Ω   4.3%

In addition, I measured the physical dimensions of the caps as follows:

Capacitance: width (mm) x height (mm), lead spacing (mm)
1500uF: 8 x 16, 3.5
1000uF: 8 x 12, 3.5
10uF: 4 x 8, 2.5

All caps are 105C rated on my board.

On my board I have 8 x 1500uF caps, 4 x 1000uF caps and 22 x 10uF caps.

Hopefully this well help the next person looking to recap a VA=503+. I'm going to look for capacitors now...

[Per Hansson]

Re: FIC VA-503+ best replacement for Vcore caps

For your information those readings mean that those capacitors are bad.
Even the "entry level" low ESR capacitors would have ESR almost 10 times lower than that...
And the Vloss percentage should ideally be under 1%

P.S: Have you done the calibration of the meter? It is done by shorting all 3 pins at power on and then following the on screen instructions.
You may want to read up on it first because depending on what firmware it has it may ask for a 100nF and a 1000nF film cap for the calibration.

[mzolli]

Re: FIC VA-503+ best replacement for Vcore caps

For your information those readings mean that those capacitors are bad.
Even the "entry level" low ESR capacitors would have ESR almost 10 times lower than that...
And the Vloss percentage should ideally be under 1%

P.S: Have you done the calibration of the meter? It is done by shorting all 3 pins at power on and then following the on screen instructions.
You may want to read up on it first because depending on what firmware it has it may ask for a 100nF and a 1000nF film cap for the calibration.

This is great information. Thank you. I'm going to try as you suggest.

[mzolli]

Re: FIC VA-503+ best replacement for Vcore caps

Now there are about 20+ 10uF left that are spread over the board. I´m probably going to swap them as well.

One note: All but one of the small electrolytic capacitors are 10uF/25V. One of them is 22uF/16V.

I replaced all the large capacitors on my VA-503+ board and it still would not POST. After replacing all the 10uF & the single 22uF capacitor, it comes right up. Success!