Single-rail vs. multi-rail power supplies?

[Yousuf Khan]

I did not raise the voltage back to where it was. Just enough to stop
the errors. I'm not saying that your errors are caused by the same thing
as mine. Just giving you something else to try.

Well, I'll keep it in mind then. When all else fails, that's worth a
shot. But of course my first solution is a new PS.

Yousuf Khan

 

[shawn]

I don't own a copy of IEC60950, so I can't copy/paste
the appropriate part. And the last time I looked, I couldn't
find a copy "floating" on the web. The keyword "SELV" comes
to mind, but that's about all I remember now.

http://www.freetechebooks.com/file-2011/iec-60950-pdf.html

 

[larry moe 'n curly]

I don't think the video is at issue at all, it's plugged into its own
private rail, and I've never had any problems with it. It's the storage
units that are having the problems.

Does the Zalman really have 4 separate rails, which would require at
least 4 separate windings for the +12V rails, or does it just have 4
separate current sense lines? Because JonnyGuru.com has found that
many PSUs advertised as being multirail have all the +12V lines
connected to the same place on the circuit board. Also the video
card probably won't be as sensitive to fluctuations from the +12V
because it has its own voltage regulator. Disk drives do, too, for
some voltages, but I don't know about the +12V for the motors.

 

[David]

http://www.freetechebooks.com/file-2011/iec-60950-pdf.html

Nice try, but it's only the first few pages.
IEC doesn't let this one out without paying for it.

Here's some pages that give you the gist of what's in the spec:

http://www.i-spec.com/IEC_60950/iec_60950.html

but to get the detailed requirements, you have to buy the spec.

SELV refers to circuits that are separated physically and electrically
from the other circuits, and do not carry a voltage more than 60V DC, or
42.5V peak AC.

 

[Yousuf Khan]

Does the Zalman really have 4 separate rails, which would require at
least 4 separate windings for the +12V rails, or does it just have 4
separate current sense lines? Because JonnyGuru.com has found that
many PSUs advertised as being multirail have all the +12V lines
connected to the same place on the circuit board. Also the video
card probably won't be as sensitive to fluctuations from the +12V
because it has its own voltage regulator. Disk drives do, too, for
some voltages, but I don't know about the +12V for the motors.

I don't know, according to this:

http://www.zalman.com/eng/product/Product_Read.asp?idx=196

"Four Independent +12VDC Outputs
Four +12VDC rails supply power independently to the CPU, VGA,
motherboard, and peripheral components for the highest level of
stability and performance. "

But that could just be marketing speak.

Yousuf Khan

 

[Yousuf Khan]

I don't know, according to this:

http://www.zalman.com/eng/product/Product_Read.asp?idx=196

"Four Independent +12VDC Outputs
Four +12VDC rails supply power independently to the CPU, VGA,
motherboard, and peripheral components for the highest level of
stability and performance. "

But that could just be marketing speak.

Yousuf Khan

The following review article seems to doubt that the four rails are
actually independent.

http://www.silentpcreview.com/article688-page1.html

Yousuf Khan

 

[Paul]

The following review article seems to doubt that the four rails are
actually independent.

http://www.silentpcreview.com/article688-page1.html

Yousuf Khan

http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story2&reid=30

http://www.hardwaresecrets.com/article/Zalman-ZM600-HP-600-W-Power-Supply-Review/402/6

It could be a single transformer with four output windings for +12V.
And four diode pairs (one pair per three legged package) for rectification
on the outputs. There are no closeup shots of the solder blobs on the wire
loom area, to see whether the 12V outputs are joined after the rectifiers
or anything.

The second reviewer, seems to be using a load tester with only two 12V loads
to use for the four outputs. The first reviewer is using a strange
loading pattern, which helps make 12V2 and 12V4 look like they're connected
together (identical voltages).

Paul

 

[Rod Speed]

larry moe 'n curly wrote

Yousuf Khan wrote

Does the Zalman really have 4 separate rails, which would require at
least 4 separate windings for the +12V rails, or does it just have 4
separate current sense lines? Because JonnyGuru.com has found that
many PSUs advertised as being multirail have all the +12V lines
connected to the same place on the circuit board. Also the video
card probably won't be as sensitive to fluctuations from the +12V
because it has its own voltage regulator. Disk drives do, too, for
some voltages, but I don't know about the +12V for the motors.

They dont, but dont need that either. The most that a rail sagging
a little does is see the drive take a little longer to get up to speed.

 

[Rod Speed]

Yousuf Khan wrote

Yousuf Khan wrote

The following review article seems to doubt that the four rails are
actually independent.

http://www.silentpcreview.com/article688-page1.html

You can check if they are just by opening the case and see
if all the 12V wires are all soldered together. I doubt they are
tho with a brand name like Zalman.