Recapping Antec SmartPower SP350 and SP400

[everell]

I have recently acquired two Antec SmartPower psu, SP350 and SP400. The SP350 required a lot of repairs before recapping. The critical 5vsb capacitor esr was greater than 99 on Blue esr meter, so high +5vsb voltage and other component failures. The SP400 critical 5vsb capacitor had esr of .86, still measuring 5 volts. Both had lots and lots of Fuhjyyu capacitors. I have replaced nearly all with Nichicon PW caps, but had to order some of those small diameter ones from topcat.

What remains to be done: the SP350 has Fuhjyyu mains 680 uf/200 volts, and the SP400 has Fuhjyyu mains 820 uF/200 volts. Does Fuhjyyu main caps also give problems big enough to require replacement?

Both psu boards had one .1 uF/50 volt cap and one .22 uF/50 volt cap. Also Fuhjyyu. Nichicon does not make low esr capacitors for these small values. I need to look at what circuits they are in to determine if a ceramic or plastic capacitor could be used, or if a general purpose aluminum capacitor would be OK. Any suggestions?

And finally, each psu got a 5vsb modification - add on board with DM311 chip. Hate to invest time and money in a psu with a loser (2 transistor circuit) for 5vsb. Here are some photos showing the add on modification board.

[etnietering]

Re: Recapping Antec SmartPower SP350 and SP400

My logisys had Fuhjyyu's on the primaries, and one of them was bulged, so I'd definitely recommend junking them for something better. I don't know about the little caps though.

[370forlife]

Re: Recapping Antec SmartPower SP350 and SP400

I have had small caps cause problems. On a sunpro raidmax 450W it would sometimes power up and sometimes not, and when it did power up it had wild voltage fluctuations. The small caps were mostly 50v, 1, 2.2, and 10uf GoldLink brand caps. Somehow just changing the small caps fixed it. I used some small rubycon's and taicon's I have scavenged over time though. UCC also makes the 50v, 1 and 2.2uf low esr caps.

[Toasty]

Re: Recapping Antec SmartPower SP350 and SP400

Everell,

I can't find the schematic or parts list for this DM311 mod of yours. I find bits of it in the Bestec posts, but it includes all the Bestec PSU components, not this circuit by itself. I thought you had posted it, I just can't locate it...

Would you point to it with a link please?

Toast

[Toasty]

Re: Recapping Antec SmartPower SP350 and SP400

There is a discussion on a question PCBONEZ raised from a month ago about using electrolytics instead of ceramics for the small values.

https://www.badcaps.net/forum/showthread.php?t=8187

Toast

[everell]

Re: Recapping Antec SmartPower SP350 and SP400

Everell,

I can't find the schematic or parts list for this DM311 mod of yours. I find bits of it in the Bestec posts, but it includes all the Bestec PSU components, not this circuit by itself. I thought you had posted it, I just can't locate it...

Would you point to it with a link please?

Toast

I don't remember ever posting just the DM311 circuit by itself - I always made a schematic for the entire 5vsb section for the particular board I was working on. Each psu is a little different, most are straight forward, but not all. The Powerman psu required a bleeder resistor to prevent oscillation when shutting down. The SeaSonic had loading problems and would not turn on until I reduced the filter capacitor which was loading it too much. Found out later SeaSonic doesn't work on all mobos I tested it with so will have to do some more "engineering" on it to find out why.

If you would like, I can work up a schematic in the next few days. Are you planning to build one for a Antec psu?

[tj2]

Re: Recapping Antec SmartPower SP350 and SP400

Found out later SeaSonic doesn't work on all mobos I tested it with so will have to do some more "engineering" on it to find out why.

If you investigate the Seasonic and make any discoveries, I'd be happy to hear about it. It might have relevance to my SS-300FS!

[i4004]

Re: Recapping Antec SmartPower SP350 and SP400

https://www.badcaps.net/forum/showth...m311#post65142
or l&c mod
https://www.badcaps.net/forum/showth...m311#post76920
and dm311 datasheet should suffice to apply it anywhere...
offcourse it's easier if everell makes custom design..hehe...

The SeaSonic had loading problems and would not turn on until I reduced the filter capacitor which was loading it too much. Found out later SeaSonic doesn't work on all mobos I tested it with

tried to load it with stuff on output, as opposed to changing the cap value to make it start?

[Toasty]

Re: Recapping Antec SmartPower SP350 and SP400

>>Both psu boards had one .1 uF/50 volt cap and one .22 uF/50 volt cap. <<

0.22uF or 22uF? A .22uF is marked 0.22uF, at least by Fuhjyyu. I checked my SP-450 cap layout sheet and I see the 0.1uF over at the TPS3510 supervisor and a 22uF over by the AC input connector. No 0.22uF anywhere...?

TN's are GP caps. Just about any 105°C cap will do fine there.

Nichicon VR or VZ would be fine there or UCC KMG. KMG would also be fine for Mains caps. Mine (1000/200) are KMG's and they were in service 3+ years 24/7 on hot system.

I only did the 'vent' caps on mine as all the others checked fine on Blue meter.

Toast

[EDIT:
"If you would like, I can work up a schematic in the next few days. Are you planning to build one for a Antec psu?"

Okay, thanks!
No. I want to turn it into a circuit board drawing for etching and downsizing.]

[everell]

Re: Recapping Antec SmartPower SP350 and SP400

Toasty, you didn't look hard enough. Take one of your SmartPower pc boards. Look at the side of the pc board where all of the output wires come out. On the left side is the small add-on pc board where fans plug in. On the right side is two toroid coils.

Now ... looking from right side to left .... parts next to the heat sink ...... first is a small TO92 case transistor (actually a TL431 regulator). Next is a 10 uF/50 volt cap. Next is a .22 uF/50 volt cap. It is under the toroid coil and behind the large 3.3 volt filter cap. Talk about something hard to get to!!! WOW. And of course - Fuhjyyu

[370forlife]

Re: Recapping Antec SmartPower SP350 and SP400

Try removing the heatsinks to get at the small parts better.

[Toasty]

Re: Recapping Antec SmartPower SP350 and SP400

Yeah. I have it drawn, laying on its side and just didn't look twice at the labeling on my drawing.

It was not replaced either.

The board mask also doesn't show that as polarized nor an electrolytic either. Mine was mounted with the (-) lead towards the heatsink. Yours?

Toast

[Toasty]

Re: Recapping Antec SmartPower SP350 and SP400

...and I'm -not- going back in there ever again...!!!


Yes, they're -all- FM's. Shoe horn and lubricant -not- included.

Another correction. I -did- replace the inputs with KMQ's. The Fuhjyyu inputs were (are) fine on value, leakage, and Blue ESR meter.

DK: 565-2956-ND - EKMQ201VSN102MP50S - $3.93 ea.

[everell]

Re: Recapping Antec SmartPower SP350 and SP400

Yeah. I have it drawn, laying on its side and just didn't look twice at the labeling on my drawing.

It was not replaced either.

The board mask also doesn't show that as polarized nor an electrolytic either. Mine was mounted with the (-) lead towards the heatsink. Yours?

Toast

Both of mine were also minus side toward the heat sink. I did buy GP Nichicon VZ replacements....but am very reluctant to change them. They sure are hard to get to! I haven't traced them. Any idea what they do?

[Toasty]

Re: Recapping Antec SmartPower SP350 and SP400

It's a decoupling cap on a line going to the fan control board from the input to the 3.3v pi filter. Its negative goes to 2 SMD resistors then to the (+) of the 10/50 cap next to it.

2 pics attached show trace to FCB.

Last pic is of solder side 5vsb critical cap and associated SMD resistor. The resistor on mine was a cold joint from factory. After having the board out and recapped, it would not start. No 5vsb. I started checking voltages and when I probed across that cap, I apparently applied enough pressure to make the connection and the 5vsb came up. Consequently reflowed and its fine.

Toast

[everell]

Re: Recapping Antec SmartPower SP350 and SP400

This might be a good psu to try the DM311 circuit on! Here is a schematic showing ALL of the parts on the add-on pc board.

[everell]

Re: Recapping Antec SmartPower SP350 and SP400

Here is the 5vsb modification procedure for the Antec SmartPower (SP350 and SP400)

1. Remove jumpers J1 and J3. They are both by the 5vsb transformer close to the edge of the pc board - on the top side (or component side) of the pc board.

2. Follow the next eleven photos showing location of all modifications on the bottom of the pc board.

[PCBONEZ]

Re: Recapping Antec SmartPower SP350 and SP400

This might be a good psu to try the DM311 circuit on! Here is a schematic showing ALL of the parts on the add-on pc board.

I missed the beginning of this. - What does the mod do?
[And what is pin 4 on the opto?]

[everell]

Re: Recapping Antec SmartPower SP350 and SP400

The first post in this thread showed that both Antec SmartPower psu were given my 5vsb DM311 modification. Toasty asked about what was on the board. So in the above posts I posted a schematic of the board, then added the photos showing how it was installed on these two psu. I dislike those two transistor 5vsb circuits as much as others dislike those Fuhjjyu brand capacitors. So I included the 5vsb mod as a part of the recapping process.

[goodpsusearch]

Re: Recapping Antec SmartPower SP350 and SP400

Why it is a bad thing the 2 transistor 5vsb circuit?