Questions on recapping a Seasonic SS-300FS

[370forlife]

Re: Questions on recapping a Seasonic SS-300FS

As far as hypermicro systems knows based on what seasonic tells them, they think it is new.

[ratdude747]

Re: Questions on recapping a Seasonic SS-300FS

I wonder if the whole 5 Vsb couldn't be completely ripped out and the PSU modded to be switched on and off via the rear switch. I rarely need to turn my machines off.

atx standard= no hard switch on/off. i tried it, the mobo has to be turned on for the system to do more than spin fans.

[PCBONEZ]

Re: Questions on recapping a Seasonic SS-300FS

He's right. .. Won't work.
Don't have +5v until PSU starts and you need +5vsb to start PSU.

[tj2]

Re: Questions on recapping a Seasonic SS-300FS

OK, perhaps I should just forget the Seasonic or use it as a hobby project to see if I might get Everell's design to work on it; maybe I will use it after a recap and an Everell mod if that's successful.

Does anyone have a suggestion for a reliable, non-killer PSU, whether or not it needs a recap? I have old equipment so I only need a 300W ATX PSU but it NEEDS to be reliable because I can't afford to have my equipment ruined by a bad PSU.

I had been buying PC Power & Cooling, but after reading here, I think I might have been wasting my money. On the other hand Seasonic, which has a reasonably good reputation here, seems to make some units that are not to be worth the (admittedly little) money either.

I have to recap my old PC Power & Cooling Turbo-Cool 300 ATX, too, but that'll be another thread and I'll post pics from the beginning.

[PCBONEZ]

Re: Questions on recapping a Seasonic SS-300FS

Does anyone have a suggestion for a reliable, non-killer PSU

Yes.
The one in this thread after you fix it.

[370forlife]

Re: Questions on recapping a Seasonic SS-300FS

If your board uses a 8 pin cpu connector and a 24 pin mainboard connector, consider this:

http://www.hypermicro.com/itemdesc.a...SAB001&eq=&Tp=

or if you only need a 4pin cpu connector

http://www.hypermicro.com/itemdesc.a...SDT009&eq=&Tp=

or

http://www.hypermicro.com/itemdesc.a...002045&eq=&Tp=

[370forlife]

Re: Questions on recapping a Seasonic SS-300FS

Yes.
The one in this thread after you fix it.

Probably better idea. Does the unit still power up? As I said before, it may have been a flaw in the design and the returned units "fixed" and re-sold.

[tj2]

Re: Questions on recapping a Seasonic SS-300FS

If your board uses a 8 pin cpu connector and a 24 pin mainboard connector, consider this:

http://www.hypermicro.com/itemdesc.a...SAB001&eq=&Tp=

I have a small stock of boards, all of which only have the 20-pin connector. The fastest of these boards is a PIII 1000 MHz. You see, I'm old-fashioned. (And, yes, I still have my slide rule, but I only use it for nostalgic reasons.)

Does the unit still power up?

I haven't tried it yet, and now I won't put it on one of my boards, but only on a PSU tester.

Yes.
The one in this thread after you fix it.

I'm pleased by your estimate of the PSU's potential, but I have a pretty long time frame for reliability. I need it to run for several years, and unattended for up to six weeks during the summer when I'm far away from the office.

I don't mind fixing it; I'm rather enjoying my new obsession. I haven't been knee deep in fixing electronics since I fixed my Kenwood TS-530S rig in 1983. Nonetheless, I still worry about my fixes until they've run for a while.

[Toasty]

Re: Questions on recapping a Seasonic SS-300FS

>>(And, yes, I still have my slide rule, but I only use it for nostalgic reasons.)<<
LOL Me too.

>>but I have a pretty long time frame for reliability<<
Then you'll be happy with the FM's and Everell's mod.

First test is plug it in to AC and measure 5vsb (purple) with meter.

Toast

[kc8adu]

Re: Questions on recapping a Seasonic SS-300FS

I don't mind fixing it; I'm rather enjoying my new obsession. I haven't been knee deep in fixing electronics since I fixed my Kenwood TS-530S rig in 1983. Nonetheless, I still worry about my fixes until they've run for a while.

do you still have that 530?
just fixed up an 830s.
great old rigs.

[PCBONEZ]

Re: Questions on recapping a Seasonic SS-300FS

Seasonics with good caps are excellent PSU's and should easily meet your time frame requirements. Their OEM models [like yours] get cheaper caps than their retail market models but AFAIK the PCB is the same. None of those recommend earlier are guaranteed to be any better than what you already have. That is NOT to say they are bad PSU's but some recapping may be required. Like the one you already have, they are good designs but sometimes have crap caps. Hi-Pro is on/off about cap quality. The ACBEL model has a whole thread devoted to it somewhere in here. It should be recapped. As I recall it has Pce-tur and you'll need lots of those 10mm caps. Of the three the Delta is the most likely to need no upgrades at all.

If you really need that level of reliability you should consider a redundant supply [which will probably require a server chassis]. Those are actually 2 [or 3] removable [hot swap] PSUs in one frame set up such that they share the load but if either one craps out the other is capable of carrying the full load.
http://cgi.ebay.com/ws/eBayISAPI.dll...m=200340919519
http://cgi.ebay.com/ws/eBayISAPI.dll...m=320397951949
[Just examples but EMAC / Zippy are an excellent brand for those. Also Sparkle.]
- !!!! Make sure what ever unit you get has wires to connect to a motherboard. Some are designed for specific cases and have slide in connectors to the chassis instead of motherboard wires. - Also some specialized ones are weird with no 3.3v or no +5vsb or I've even seen one with a 48v rail.

-Or- I would get [These are models you shouldn't even need to open up.]
Corsair
http://www.newegg.com/Product/Produc...82E16817139008
RETAIL Seasonic
http://www.newegg.com/Product/Produc...82E16817151073
Sparkle
http://www.newegg.com/Product/Produc...82E16817103012

If you use a UPS and you have a PSU with any kind of PFC you need to verify your UPS is a TRUE sine wave unit. The 'simulated' sine wave units are an old cheap design and they don't work and play well with PFC. [Which wasn't common when they were designed]. - The PFC's response to the 'fake' sine wave is to drive voltage in the first PSU stage high and sometimes it's high enough to exceed the voltage rating on the mains caps or to send too much current through something else.

.

[PCBONEZ]

Re: Questions on recapping a Seasonic SS-300FS

>>(And, yes, I still have my slide rule, but I only use it for nostalgic reasons.)<<
LOL Me too.

Me Three. - Still got it. - But I forgot how to use it like 25 years ago.

[tj2]

Re: Questions on recapping a Seasonic SS-300FS

do you still have that 530?
just fixed up an 830s.
great old rigs.

Yes, I still have the 530. Since I'm no longer on the air, I thought about selling, but I feel nostalgic about 530, too.

[tj2]

Re: Questions on recapping a Seasonic SS-300FS

>>(And, yes, I still have my slide rule, but I only use it for nostalgic reasons.)<<
LOL Me too.

>>but I have a pretty long time frame for reliability<<
Then you'll be happy with the FM's and Everell's mod.

First test is plug it in to AC and measure 5vsb (purple) with meter.

Toast

Great! OK, it looks like there's some serious fun ahead for me.

I'll check the 5 Vsb and post when I'm back at work.

[tj2]

Re: Questions on recapping a Seasonic SS-300FS

If you really need that level of reliability you should consider a redundant supply [which will probably require a server chassis]. Those are actually 2 [or 3] removable [hot swap] PSUs in one frame set up such that they share the load but if either one craps out the other is capable of carrying the full load.

I hadn't considered that. I'll check it out, though my old PC Power & Cooling kept the thing running 24/7 for six years, and my other unit has a Sparkle that's been running 24/7 for nearly ten years.

If you use a UPS and you have a PSU with any kind of PFC you need to verify your UPS is a TRUE sine wave unit. The 'simulated' sine wave units are an old cheap design and they don't work and play well with PFC. [Which wasn't common when they were designed]. - The PFC's response to the 'fake' sine wave is to drive voltage in the first PSU stage high and sometimes it's high enough to exceed the voltage rating on the mains caps or to send too much current through something else.

Yikes! I didn't know that. Thanks for pointing it out. I do have a UPS; it's an APC Smart-UPS, bought in late 2000. I'll have to check its output.

Quote:
Originally Posted by Toasty
>>(And, yes, I still have my slide rule, but I only use it for nostalgic reasons.)<<
LOL Me too.

Me Three. - Still got it. - But I forgot how to use it like 25 years ago.

Amazingly, there are collectors of old rules, some of which go for several hundred dollars these days. You can find instructions online to refresh your memory if you ever feel nostalgic. I had forgotten how good my eyes used to be! Now I need a magnifier to see the small hairline well enough to get anything like the correct answer.

[PCBONEZ]

Re: Questions on recapping a Seasonic SS-300FS

Yikes! I didn't know that. Thanks for pointing it out. I do have a UPS; it's an APC Smart-UPS, bought in late 2000. I'll have to check its output.

I don't think it says on the unit but if you have the exact model number you can look it up at APC's site. The 'Smart' units I've looked up were true sine wave but there may be exceptions.
-
When I said old design I didn't mean old UPS units. Some units may still be being built with those designs. They take fewer parts and are less expensive to build than true sine wave units. In the 'old days' PFC was uncommon in anything other than a server so it was a way to build inexpensive UPCs for home and office use. There wasn't a problem until home and office PCs started to move to PFC type PSUs. Now you have to pay attention.
-
On 115v line voltage, it can, but exceeding the input voltage on the PSU is a little less likely. I've seen the input voltage measured [Active PFC, 115 line, simulated sine wave UPS] at 198 volts. Mains caps in PSUs are sometimes 200v caps so that's like a skin'o'de'tooth margin for error and fluctuations in mains voltage could push it over the top. PSUs with 220v mains caps are safer but still maybe iffy. If they have 250v mains caps there is probably nothing to worry about.
-
If using 220v mains power it is much more of a problem. [Though at the moment I can't remember why it's worse.]
-
When I learned of all this I had to replace 3 of my UPS units. I wasn't too happy about that. Some of my stuff [including one of those 3 units] runs on 220v and 220v UPS units are hard to find in the US.
.

[PCBONEZ]

Re: Questions on recapping a Seasonic SS-300FS

*Mains caps may not be the 'limiting component' in all PSUs.
It's just the easiest one to see without drawing out the circuit and doing the math.

[everell]

Re: Questions on recapping a Seasonic SS-300FS

This was my SeaSonic SS-250FS before modification. It does not have APFC. The 5vsb was measuring around 10 volts.

[everell]

Re: Questions on recapping a Seasonic SS-300FS

Here it is after modification

[everell]

Re: Questions on recapping a Seasonic SS-300FS

These are my notes on the modification