Re: [OT] ATX-PSU and amperage on connectors...

[Michelle Konzack]

Hello Tony,

Am 2008-03-03 09:06:55, schrieb Tony van der Hoff:
> On 29 Feb at 1:21 Michelle Konzack <[EMAIL PROTECTED]> wrote in
> message <[EMAIL PROTECTED]>
> > This AWG thing is nice, since I don not know I in Europe... I am counting
> > in mm²
> 
> http://www.reuk.co.uk/AWG-to-Square-mm-Wire-Size-Converter.htm

Thats realy cool...

Thanks for the link
Greetings and nice Day
Michelle Konzack
Systemadministrator
24V Electronic Engineer
Tamay Dogan Network
Debian GNU/Linux Consultant


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Re: [OT] ATX-PSU and amperage on connectors...

[Michelle Konzack]

Hello Again,

Am 2008-02-28 19:43:01, schrieb Henrique de Moraes Holschuh:
> *If* every ATX12V PSU out there implements these requirements properly, all
> I can say is that they are NOT good enough.  OTOH, if the bog-standard
> ATX12V PSU you get from China and Taiwan are not following all the
> requirements properly, then maybe they are good enough.

I have tested last weekend some of the Step-Down-Converter chips (I
have ordered several Evaluation Boards) and was realy surprised about
the quality of the Maxim and National Regulators...

They are all without any exception better as all of my 78 AC-PSUs (200W
to 900W) I have here and tested under a REAL environement...

So, if I have found a Reseller for InfraRed soldering Equipment, I will
order free samples  :-)  of the chips and build my first 24V-DC-PSU.

> DC inputs are always MUCH better since they have a lot less high-frequency
> noise than the AC power grid.  So you have to filter out less noise in the
> first place.  That's why people like -48VDC and -24VDC power supplies so
> much in anything but the consumer marketplace.

The4 waving is much more less then at the AC-PSUs (the ATX12V spec is
talking about 60-120mV) I have always (all Voltages) less then 30mV.

> BTW: if this is the kind of stuff you are going to leave in the field inside
> an airtight box, did you remember to add some EMP shielding and surge
> protection?  Otherwise, the first time you get an electrical storm dropping
> a lightning bolt near your box, the entire thing will fry.

I will use the normal ATX-PSU case and a special Mini-ATX-PSU for 1U
racks, but for this I have not found a specification about the size.

> > I am simulation some PIGs on my programmable Load...  :-)
> 
> Make these PIGs switch on-and-off at high frequencies, with some minor
> filtering to simulate the motherboard VR, and you will have the load a
> modern CPU does :p

:-)

Currently I have my Opteron 140 running on a test installation...

Compiling a Kernel (3.3V line is increasing the consumation drasticly),
then do a "startx" to see what happen if my Matrox G450 Dual-Head must
work a little bit...

> My laptop actually *sings* in high frequencies because some of the crap in
> the mainboard is not phisically stabilized enough and ressonates due to the
> high-frequency load changes :P  It is not induced noise in the speakers, the
> components actually make noise because they are vibrating at high
> frequencies(!).  You can imagine the load profile that causes such a thing.
> Must have a RMS power factor close to zero...
> 
> I will get a glue pistol one of these days and cover the damn chips and
> capacitors with it to see if that dampens the noise enough to not bother me.
> Drat :-)

I have had the same problem with ma IBM TP570...
 and solved it with a glue pistole too!

> The links point you to online up-to-date ATX PSU specs.

I will look @it

> Well, the open hardware crowd could help you, I think.
> http://en.wikipedia.org/wiki/Open_source_hardware#External_links has links
> to many open hardware sites.

This is very interesting for me...

> If you don't use the standard connectors, you can have different power
> requirements for them (just use high-quality connectors made for power
> transfer when dealing with power transfer, and made for signal transfer when
> dealing with signal transfer).

I use only the standard connectors from the AC-PSUs

> Otherwise, use the rates specified in the spec.  They ask for a 18A type
>  connector even when you won't make more than 5A available there,
> because a conector of that type with less than 18A must be made of shinny
> crap instead of real metal :)

ACK

> You can get high quality stuff from China, but it is not easy.  Just get

Right, and since I am on , I get
updated newsletters but if you want too buy there, the minimum
quantity will be 1000 pieces.

> them from Europe or the USA because they either make it well, or do the
> quality checks on the chinese stuff.

I have found some European manufactureres but it does not help, if a
420Watt 24V-DC-PSU cost 200 Euro...
> The possibilities are endless ;-)

I have already heavy Equipment and if peoples visit me, they are
thinking, I am making a Science-Fiction Film @home...

Most peoples have never seen such professional equipment and of course
you should never tell them how much it cost...  they will never believe
it (my experience; Most I have bought on real or internet auctions, so
the Insurance price would be arround 200.000 Euro where I have payed
only 30.000 Euro)

> I'd kinda expect to find ready-made DC-DC PSUs that do it for the telecomm
> market, but they won't be cheap at all.

Not more neccesary, since currently I am using a "National" Step-Down
Regulator which make 25A on 12V and it works heavyly stable...

The Evaluation Board cost only 36 US$ and then I have buyed in germany
some new parts (17 Euro) to increase the Output-Voltage f

Re: [OT] ATX-PSU and amperage on connectors...

[Kevin Mark]

On Fri, Feb 29, 2008 at 02:21:07AM +0100, Michelle Konzack wrote:
> Hello Douglas,
> 
> Am 2008-02-27 20:52:19, schrieb Douglas A. Tutty:
> > Here are the wire sizes according to my copy of the 2002 Canadian
> > Electrical cord (still in force), table 12 "Allowable Ampacity of
> > Flexible Cord and Equipment Wire (Based on Ambient Temperature of 30C"
> > Note that cables of 4 or more wires (e.g. if you shrink-wrap 4 drive
> > wires together) would be 80%.
> > 
> > AWG Amp
> > ===
> > 26  1
> > 24  2
> > 22  3
> > 20  4
> > 18  6
> > 16  8
> > 14  17
> 
> This AWG thing is nice, since I don not know I in Europe...
> I am counting in mm²
Hi,

I googled and found this[0]:

gauge (ga) [3]
a traditional unit measuring the diameter (or the cross-sectional
area) of a wire. Various wire gauge scales have been used in the U.S.
and Britain. In traditional scales, larger gauge numbers represent
thinner wires. (For very thick wires, repeated zeros are used instead of
negative numbers, so gauges 00, 000, and  represent -1, -2, and -3,
respectively.) In the American Wire Gauge (AWG) scale,  gauge
represents a wire having a diameter of 0.46 inch and 36 gauge represents
a diameter of 0.005 inch (5 mils). Diameters for the other gauges are
obtained by geometric interpolation, meaning that the ratio between
successive diameters is a constant, except for necessary roundoff. Thus
n gauge wire has a diameter of .005·92((36-n)/39) inch. The metric wire
gauge number is equal to 10 times the diameter of the wire, in
millimeters; thus a metric 8 gauge wire has diameter 0.8 millimeters. A
table of wire gauge equivalents is provided.

The above formula did not paste correctly:
 (36-n)
  
   39
wire gauge(n)=0.005*92^   Inches

And this references this[1]:
Gauge |Washburn|British |Birmingham|American
Number| & Moen |Imperial|or|(A.W.G)
  ||Standard|Stubs |or
  ||(S.W.G) |  |Brown &
  |||  |Sharpe
14| .0800" |.080"   |.083" |.0640"
15| .0720" |.072"   |.072" |.0570"
16| .0625" |.064"   |.065" |.0508"
17| .0540" |.056"   |.058" |.0452"
18| .0475" |.048"   |.049" |.0403"
19| .0410" |.040"   |.042" |.0358"
20| .0348" |.036"   |.035" |.0319"
21| .0317" |.032"   |.032" |.0284"
22| .0286" |.028"   |.028" |.0253"
23| .0258" |.024"   |.025" |.0225"
24| .0230" |.022"   |.022" |.0201"
25| .0204" |.020"   |.020" |.0179"

HTH,
Kev
[0] http://www.unc.edu/~rowlett/units/dictG.html
[1] http://www.unc.edu/~rowlett/units/scales/wiregauge.html

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Re: [OT] ATX-PSU and amperage on connectors...

[Douglas A. Tutty]

On Sun, Mar 02, 2008 at 01:30:43PM +0100, Michelle Konzack wrote:
> after rereading the ATX12V specification I have some questions as
> non-native english speaker...  :-)
> 
> Am 2008-02-22 11:51:59, schrieb Douglas A. Tutty:
> > So the only trick for your design is what plugs from the PSU are on
> > which 12V bus.  Here's the breakdown:
> 
> Right...
> 
> In the ATX12V specification (version 2.2) it is written:
> 
> 8<--
> 1.2.1. Increase +12 VDC output capability
>   System components that use 12V are continuing to increase in power.
>   In cases where expected current requirements is greater than 18A a
>   second 12 V rail should be made available. ATX12V power supplies
>   should be designed to accommodate these increased +12 VDC currents.
> 8<--
> 
> The Iout on 12V2 is between 13A (200W PSU) and 16A (450W PSU) from
> the specs.

Then that will fit on the one 12V2 rail since its less than 18A.  My
guess for the reason for the 18A limit is to limit the size of the wire
required.  
> 
> 8<--
> 1.2.2. Main Power Connector
>   The 2 x 10 main power connector has been replaced by a 2 x 12
>   connector. This was made to support 75 watt PCI Express*requirements.
>   Pinout assignments are based on the SSI recommendation. With the added
>   12V, 5V, and 3.3V pins the need for an Aux Power connector is no
>   longer needed and the guidance for this connector has been removed.
> 8<--
> 
> I assume the AUX-Power connector was the 6pin connector with 3x GND,
> 2x 3.3V and 1x 5V

Don't know.  I went from a PSU with only a single connector to the MB
and the drive connectors (on my 486, a P-75, and a P-II), to my athlon64
with the PSU for which I sent specs.  No doubt there were PSU specs
in-between which I have never seen.
> 
> 8<--
> 1.2.3. Separate current limit for 12V2 on the 2x2 connector
>   The 12V rail on the 2 x 2 power connector should be a separate current
>   limited output to meet the requirements of UL and EN 60950.
> 8<--

They're talking about a current limit for this one connector, which
comes off of a bus with a, presumably, higher current limit.
> 
> And here it begins where I do not know... because:
> 
> 8<--
> 3.2.3.1. ATX12V Configurations
>   Table 3. Typical Power Distribution for a 250 W ATX12V Configuration
>  Min. Max.Peak
>  Current  Current Current
> Output   (amps)   (amps)  (amps)
> +12 V1DC(1)  18   9
> +12 V2DC (1, 2)  113  16.5
> +5 VDC   0.3  12
> +3.3 VDC 0.5  14
> -12 VDC  00.3
> +5 VSB   02.5 3.5
> 
>   Note: Total combined output of 3.3 V and 5 V is 115W
> Peak currents may last up to 17 seconds with not more than
> one occurrence per minute
>   (1) 12V1DC and 12V2DC should have separate current limit circuits
>   to meet 240VA safety requirements.
>   (2) 12V2DC supports processor power requirements and must have a
>   separate current limit and provide 16.5A peak current for
>   10 ms; minimum voltage during peak is > 11.0 VDC
> 8<--
> 
> So note (2) say: "12V2DC supports processor power requirements" which
> mean the ATX-Connector is on 12V2.
> 
> Is this right?

Don't know.  What did the specs for my PSU say?  Remember, there are two
connectors to the MB now, both called "ATX" just to be confusing.  
> 
> Then I have a problem to understand HOW 13A on 12V2 can support the ATX-
> Connector and the 2x2 12V connector.  This make for me no logic...
> 
> E.g. 5V + 3.3V can be only 115W, but 12V2 is 13A = 159A => the rest is
> then maximum 44W which mean, a maximum of 3.66A for the 2x2 connector.
> 
> From the ATX12V specification:
> 
> 8<--
> 4.5. DC Connectors
> 
> 4.5.1. ATX Main Power Connector
>   + 3.3V  => taken from 12V2
>   + 5  V  => taken from 12V2
>   +12  V  => taken from 12V1 (!!!)
> 
> 4.5.2. +12 V Power Connector
>   +12  V  => taken from 12V2
> 
> 4.5.3. Peripheral Connector(s)
>   + 5  V  => taken from 12V2
>   +12  V  => taken from 12V1 (!!!)
> 
> 4.5.4. Serial ATA Power Connector
>   + 3.3V  => taken from 12V2
>   + 5  V  => taken from 12V2
>

Re: [OT] ATX-PSU and amperage on connectors...

[Douglas A. Tutty]

On Mon, Mar 03, 2008 at 09:06:55AM +, Tony van der Hoff wrote:
> On 29 Feb at 1:21 Michelle Konzack <[EMAIL PROTECTED]> wrote in
> message <[EMAIL PROTECTED]>
> > > AWG   Amp === 26  1 242 223 204 186 16
> > > 8 1417
> >
> > This AWG thing is nice, since I don not know I in Europe... I am counting
> > in mm?
> 
> http://www.reuk.co.uk/AWG-to-Square-mm-Wire-Size-Converter.htm

And just for reference, here in N.A., standard lamp cord is 18 AWG.
I've never been out of N.A. but perhaps someone who has seen both N.A.
lamp cord and Euro lamp cord could comment so that Michelle has some
idea what I'm talking about.  Its a tactile thing.  Tell me that I need
wire of so-many-square-mm and I'll be doing the pi-are-squred thing to
get the radius, doubling that to get the diameter so I can actualy go
looking.

Doug.


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Re: [OT] ATX-PSU and amperage on connectors...

[Tony van der Hoff]

On 29 Feb at 1:21 Michelle Konzack <[EMAIL PROTECTED]> wrote in
message <[EMAIL PROTECTED]>

> Hello Douglas,
>
> Am 2008-02-27 20:52:19, schrieb Douglas A. Tutty:
> > Here are the wire sizes according to my copy of the 2002 Canadian
> > Electrical cord (still in force), table 12 "Allowable Ampacity of
> > Flexible Cord and Equipment Wire (Based on Ambient Temperature of 30C"
> > Note that cables of 4 or more wires (e.g. if you shrink-wrap 4 drive
> > wires together) would be 80%.
>> 
> > AWG Amp === 26  1 242 223 204 186 168 14
> > 17
>
> This AWG thing is nice, since I don not know I in Europe... I am counting
> in mm²

http://www.reuk.co.uk/AWG-to-Square-mm-Wire-Size-Converter.htm


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Buckinghamshire, England

Re: [OT] ATX-PSU and amperage on connectors...

[Michelle Konzack]

Hello Douglas,

Am 2008-02-27 20:52:19, schrieb Douglas A. Tutty:
> Here are the wire sizes according to my copy of the 2002 Canadian
> Electrical cord (still in force), table 12 "Allowable Ampacity of
> Flexible Cord and Equipment Wire (Based on Ambient Temperature of 30C"
> Note that cables of 4 or more wires (e.g. if you shrink-wrap 4 drive
> wires together) would be 80%.
> 
> AWG   Amp
> ===
> 261
> 242
> 223
> 204
> 186
> 168
> 1417

This AWG thing is nice, since I don not know I in Europe...
I am counting in mm²

> Elecrically, these would be fine with 26 or 24 AWG without overheating
> the insulation.  However, you don't provide inrush current requirements

Since I do not know them, I know only, what is written on the Drives.

> of the device.  Too much resistance in the wire could end up
> undervoltaging the drive motors.  

I know.

> Put the two most power-hungry devices on the same power cable: Teac-CDR
> and the AsusTek DVD for a total of 3.3A each of 5v and 12v, and you
> would need 20 AWG wire.  However, as I said in a previous entry, for
> moveable wire, the minimum (unless you went with some high-tech
> mechanically supported wire) would be 18 AWG (which is what my PSU's
> happen to use).

It seems, that the 3 cables (3 HDD connector on each cable)
on my 600W PSU has cables of 0.5mm²

> > one of my problems is, that most DC-DC-Step-Down-regulators do not
> > support High-Voltage entry and most are limited to 14-16 Vin.
> > 
> > This mean, I need some High-Power (>=25A) DC-DC Step-Down regulators to
> > get 12Vout from 18-30Vin and then I can build the +5V and +3.3V from it.
> 
> 
> And there will go your efficiency.  You could probably get 70-80% with
> one DC-DC converter but if you do two in a row, there's two places for
> waste.  If you have to go that route, its probably no more waste to use
> a true-sine-wave inverter to turn your 24VDC to 110VAC and then use a
> normal AC PSU.

Not realy right, since according to ATX12V the AC PSU should have an
efficiency of at least 66%.  Most standard AC PSUs have around 80%

So if my 24/12V DC Step-Down-Regulator make arround 90% and the 3.3/5V
DC Step-Down-Regulators arround the same, I have effectiv 81%...

If I use a DC/AC sin-wave converter, it will have not more then 80%
which result in a effectiv efficiency between 53% to 64%.

Realy bad...

HOWEVER, I have the need to be OVER 80%...

> > For what is the 8pin power connector?  --  I have never seen it
> 
> Don't know.  Don't want to open my box while I writing email to look.
> What does the ATX speck on Wikipedia say?

This connector is not mentionedin ATX12V since it is currently NO
standard...

> IIRC, there's a single-chip solution for the -5 and -12V that comes in a
> TO-220 package (looks like a normal 1A regulator), one pin regulated +5
> (or +12V) in, centre pin common (connected to heat-sink), third pin is
> -5V (or -12V) output.  I know its linear but it doesn't really matter
> for 0.3A and 0.8A.  IIRC, they were made by TI.  

Dallas does the same thing but smaller...  cost arround 0.80US$/chip

> I needed these when I designed and built my own computer back in 1986.
> It had 8 Zilog Z-80 8MHz CPUs with an 8-phase clock running at 64 MHz.

8Mhz?  the standard version was only 2 and 4 MHz and the INCOMPATIBLE
C-MOS version 4 and 6 MHz.

How do you have gotten running this pig with 8 MHz?

Note:  I have bought the Sinclai ZX-81 in 1983 and in 1984 I have bought
   my first "real" CPU building my own computer...  Before I have
   used only 8038/39/49 (Single-Chip-Computers with many I/O and
   AD/DA)

> Everything was TTL including the static RAM (64K for each processor).  I
> started on it after reading two books for the first time: 2001 A Space
> Odessy, and Mitchner's Space.  Got me (a math flunky) into learning
> about calculating Hohmann transfer orbits (of all things) and I needed a
> 128-bit calculator...  Output was in hex, input was in hex.  Programming
> was in Z-80 machine code.  No secondary storage (who could afford
> that?).  PSU was a 30# (that I rewound) transformer putting out 50A
> rectified 8VDC then running to linear regulators.  PSU weighed about
> 50#, connected with 4AWG welding cables to the computer.  Bascially, the
> PSU was a welding unit by the time I had it made.  Don't ask me the
> efficiency.  It sure made a nice BBVVVWWWOOOM when I turned it
> on.  Just incase the electrolytic caps blew (each about the size of a
> 500 Ml Mason Jar), I built the cases out of the external cladding of a
> hot-water-tank: 14 gauge steel. :)

:-)

> Its amazing what ones parents let one build in the basement when they
> don't know what one can find in an old TV...

...  You are like me!   Oh, in 2 Month I am 40y.

> At what voltage?  At 3V that's 30A.  My MB doesn't have any 10AWG wire
> going to it, but then again, this may be why there's extra power plugs
> that go to the MB,  24-pin then the 4-pin.  Each wire on the 

Re: [OT] ATX-PSU and amperage on connectors...

[Michelle Konzack]

Hello Douglas,

after rereading the ATX12V specification I have some questions as
non-native english speaker...  :-)

Am 2008-02-22 11:51:59, schrieb Douglas A. Tutty:
> So the only trick for your design is what plugs from the PSU are on
> which 12V bus.  Here's the breakdown:

Right...

In the ATX12V specification (version 2.2) it is written:

8<--
1.2.1. Increase +12 VDC output capability
  System components that use 12V are continuing to increase in power.
  In cases where expected current requirements is greater than 18A a
  second 12 V rail should be made available. ATX12V power supplies
  should be designed to accommodate these increased +12 VDC currents.
8<--

The Iout on 12V2 is between 13A (200W PSU) and 16A (450W PSU) from
the specs.

8<--
1.2.2. Main Power Connector
  The 2 x 10 main power connector has been replaced by a 2 x 12
  connector. This was made to support 75 watt PCI Express*requirements.
  Pinout assignments are based on the SSI recommendation. With the added
  12V, 5V, and 3.3V pins the need for an Aux Power connector is no
  longer needed and the guidance for this connector has been removed.
8<--

I assume the AUX-Power connector was the 6pin connector with 3x GND,
2x 3.3V and 1x 5V

8<--
1.2.3. Separate current limit for 12V2 on the 2x2 connector
  The 12V rail on the 2 x 2 power connector should be a separate current
  limited output to meet the requirements of UL and EN 60950.
8<--

And here it begins where I do not know... because:

8<--
3.2.3.1. ATX12V Configurations
  Table 3. Typical Power Distribution for a 250 W ATX12V Configuration
 Min. Max.Peak
 Current  Current Current
Output   (amps)   (amps)  (amps)
+12 V1DC(1)  18   9
+12 V2DC (1, 2)  113  16.5
+5 VDC   0.3  12
+3.3 VDC 0.5  14
-12 VDC  00.3
+5 VSB   02.5 3.5

  Note: Total combined output of 3.3 V and 5 V is 115W
Peak currents may last up to 17 seconds with not more than
one occurrence per minute
  (1) 12V1DC and 12V2DC should have separate current limit circuits
  to meet 240VA safety requirements.
  (2) 12V2DC supports processor power requirements and must have a
  separate current limit and provide 16.5A peak current for
  10 ms; minimum voltage during peak is > 11.0 VDC
8<--

So note (2) say: "12V2DC supports processor power requirements" which
mean the ATX-Connector is on 12V2.

Is this right?

Then I have a problem to understand HOW 13A on 12V2 can support the ATX-
Connector and the 2x2 12V connector.  This make for me no logic...

E.g. 5V + 3.3V can be only 115W, but 12V2 is 13A = 159A => the rest is
then maximum 44W which mean, a maximum of 3.66A for the 2x2 connector.

From the ATX12V specification:

8<--
4.5. DC Connectors

4.5.1. ATX Main Power Connector
  + 3.3V  => taken from 12V2
  + 5  V  => taken from 12V2
  +12  V  => taken from 12V1 (!!!)

4.5.2. +12 V Power Connector
  +12  V  => taken from 12V2

4.5.3. Peripheral Connector(s)
  + 5  V  => taken from 12V2
  +12  V  => taken from 12V1 (!!!)

4.5.4. Serial ATA Power Connector
  + 3.3V  => taken from 12V2
  + 5  V  => taken from 12V2
  +12  V  => taken from 12V1 (!!!)

4.5.5. Floppy Drive Connector
  + 5  V  => taken from 12V2
  +12  V  => taken from 12V1 (!!!)
8<--

But A friend of me has tested the 2x2 12V P4-Connector and it hit
arround 16A using a P4/4000 which mean, even a 450W PSU (from the
specs) would not support this PIG since 12V2 has only 16/19A.

Even my CobaKing VP-420-5120 with 20A on 12V1 and 18A on 12V2 will
be killed.

> 8 pin 12V power connector: pins 1 & 2 are from bus 1, pins 3 & 4 from
> bus 2.

This connector is not mentioned in the ATX12V specification...

> One PCIe 6 pin connector is on bus 1, the other PCIe 6 pin connector is
> on bus 3 (these are for one or two video cards that need the extra
> power)

This connector is not mentioned in the ATX12V specification...

Since I try to create a module 24V DC ATX PSU, I am thinking on:

1. ATX Pow

Re: [OT] ATX-PSU and amperage on connectors...

[Michelle Konzack]

Hello Henrique,

Am 2008-02-23 18:00:39, schrieb Henrique de Moraes Holschuh:
> Well, I recommend you go to extreme levels of output harmonics filtering,
> that alone will increase system stability a damn great deal.  Some tests
> using memory bit-rot testing a few years go (either by Ars Technica, or
> Tom's, I don't recall) nicely illustrated why one would want to do so.

In the specification "ATX12V" version 2.2 from 2005 is all documented
what is required.  Some of the requirements affect only the AC-PSUs and
not DC-PSU's...

I have for example a 3.3V Step-Down regulator which support 100A and you
can put a 100.000µF Electrolyt condensator on it and then PowerOn the PIG.

I was realy surprised about this High-Integrated MOSFET Step-Down
regulator and its stability.  I am using an 60MHz Oszilloskope with
memory and the stabilization was inside the ATX12V requirements.

And yes, Filtering the 24Vin is heavy...  since I have no real
experience with it and need some stuff to read.

Can you suggest Literature in english or german?

> And don't think for a single moment that you are designing for linear loads.
> Computers are [EMAIL PROTECTED]@[EMAIL PROTECTED] unhelpful loads, and the 
> more efficient the

I am simulation some PIGs on my programmable Load...  :-)

OK, currently I have only 3.3V stuff availlable, but It seems, I have
to build a test-environement.  (I am using an USB-connected 48-Port
IO-Card which drive programmable loads from 0 to 100A and can switch
in less then 5ms, which is maybe not enough)

> power-saving features in use in a system, the worse its load profile is when
> it comes to harmonics.

...

> > Does anyone know, where I can get the specifications for it?
> 
> Yes.  http://en.wikipedia.org/wiki/ATX, look at the external links section.

I have gotten from two peoples the ATX12V sepecs, one v1.1 from 2000
and one 2.2 from 2005 and it seems, there is all described what I
should know...

It rest only the REAL amperage on the several connectors...

I have already written it in a previosly (initial?) message that I want
to build the DC-PSU modular, which mean, if you want only to power the
Mainboard since it is a router and the HDD is a CF-Card on the MB, you
will need only the ATX-Module which could be between 60 and 100 Watt.

Oh, currently I am preparing some infos (only provisory) on



since I have the need for complete 36 DC-PSU's and I do not realy like
to develop them only for me since it is quiet expnsive for only 36
DC-PSUs.

> > How many ampers must a cable support?
> 
> Cable choice depends on cable length, and acceptable voltage drop at given
> load levels.  And you need to factor in in-rush and start current too if
> they are non-trivial (and they are non-trivial for disks, fans, and anything
> with high-drain CPUs or huge ammounts of RAM).

There are some real weird things in the ATX12V specification, since some
cables of my 600W AC-PSU have only 0.75mm² or 1.0mm² cables (arround 40cm
long) which definitivly do not support more then 10A whithou being
transformed into a heating-cable but the connectors should support
3.3V/18A or 5V/24A on the AUX Power connector.

> If you play the el-cheap-o game with the cables and electronics, you will
> get "nice" surprises when your systems face their first thermal challenge on
> the form of an unusual hot (or cool) day.

Thats not my route...

I can buy DC-DC-Converters from China but I have never seen sone, which
have an efficiency OVER 80% (ATX12V is talking about 66% but for AC PSUs
which are a VRY BIG no for my usage in Photopholtaik-Systems)

In the USA there are some Manufacturer which have ATX-Style DC-PSUs but
they cost between 320 and 580 US$.

I have currently not checked the Link from the UK, but I will try it
today.  (currently I have no HSDPA access...  do not know why)

So, I have found my microchips (e.g., High-Efficiency Step-Down
Regulators, Sequencers, OVP, and more) from Maxim, Dallas, NXP, AD and
others which fit my requirements.

The MAX8655 is one example...   But you need to solder them InfraRed or
something similar, which should no problem for me...   guess why!

The only thing which is currently not solved is the 24 Vin (18-30V) to
12Vout (and between 10 and 50A) which must be very stable and resistible
agains voltage waveing from the input...  If this problem is solved, it
is possible to produce an DC-PSU with 300W (out) for less then 60 Euro.

Also I try to get an experience with UPS-Electronic and I am searchin
for this highly intergated solutions, which mean, I wan to put an USB
connector into the PSU which can be connected to a free USB connector
on the Mainboard and be read like any other UPS...  so the 24Vin can
be whatched.  There would be an solution for a DS80C411 which can
controll the whole DC-PSU and pull the data out of the USB-Port but
I think, this can be an extra module in the C-PSU.

Thanks, Greetings and nice Day
Michelle Kon

Re: [OT] ATX-PSU and amperage on connectors...

[Douglas A. Tutty]

On Sat, Feb 23, 2008 at 02:07:28PM +0100, Michelle Konzack wrote:
> Am 2008-02-22 11:51:59, schrieb Douglas A. Tutty:
> > Hi Michelle
> > 
> > First,  you do know that one can purcase DC ATX PSUs?
> 
> Yes but with an efficienci horible...  40-70% only...
> 
> I am working with chips from Dallas, Maxim, NXP and LM and get over 85%.
> And of cources, if you need a Vin of 24V (18-32V) you are lost.
> 
> > Second,  the individual drives don't take much power so I think the wire
> > size is for mechanical support, I wouldn't go with less than 18 AWG.
> 
> I am not realy sure about this since I have for example:

Here are the wire sizes according to my copy of the 2002 Canadian
Electrical cord (still in force), table 12 "Allowable Ampacity of
Flexible Cord and Equipment Wire (Based on Ambient Temperature of 30C"
Note that cables of 4 or more wires (e.g. if you shrink-wrap 4 drive
wires together) would be 80%.

AWG Amp
===
26  1
24  2
22  3
20  4
18  6
16  8
14  17

> 
> +5   V +12   V
> CD-Rom  noname   0.35A   1.7 A
> CD-Rom  Teac CD-512E 1.5 A   1.3 A
> CD-Rom  Teac CDR-55S 1.8 A   1.8 A
> 
> DVD-Rom AsusTek E616A1.5 A   1.5 A
> 
> HDD IDE IBM DHEA-38451   0.32A   0.26A
> HDD SCSIIBM DDRS-39130   0.55A   0.65A
> HDD SCSIIBM DDRS-34560   0.55A   0.65A
> HDD SATA2   Hitachi HDT725032VLA360  0.73A   0.64A
> 
> Iomega ZIP 100   0.8 A
> 

Elecrically, these would be fine with 26 or 24 AWG without overheating
the insulation.  However, you don't provide inrush current requirements
of the device.  Too much resistance in the wire could end up
undervoltaging the drive motors.  

Put the two most power-hungry devices on the same power cable: Teac-CDR
and the AsusTek DVD for a total of 3.3A each of 5v and 12v, and you
would need 20 AWG wire.  However, as I said in a previous entry, for
moveable wire, the minimum (unless you went with some high-tech
mechanically supported wire) would be 18 AWG (which is what my PSU's
happen to use).

> 
> So if I take only the AsusTek DVD and the SATA2 disk which are two of
> the latest models, then the 4pin HDD connector need already 
> 
> 12V 2.22A   =  26.64 Watt
>  5V 2.14A   =  10.70 Watt
>   ---
>37.14 Watt
> 
> And if I see my "Enhance Electronics Co. Ltd" 300Watt PSU which has
> 
>  20pin  ATX connector
>   6pin  ePCI connector
>   4pin  P4 connector
>   2 cableswith three HDD connectors
>   1 cable with two HDD and one Floppy connector
> 
> + 3.3V  28  A \ 180 Watt \
> + 5  V  30  A /  | 279 Watt
> +12  V  15  A/
> 
> + 5  Vsb 2  A
> -12  V   0.8A
> - 5  V   0.3A
> 
> one of my problems is, that most DC-DC-Step-Down-regulators do not
> support High-Voltage entry and most are limited to 14-16 Vin.
> 
> This mean, I need some High-Power (>=25A) DC-DC Step-Down regulators to
> get 12Vout from 18-30Vin and then I can build the +5V and +3.3V from it.


And there will go your efficiency.  You could probably get 70-80% with
one DC-DC converter but if you do two in a row, there's two places for
waste.  If you have to go that route, its probably no more waste to use
a true-sine-wave inverter to turn your 24VDC to 110VAC and then use a
normal AC PSU.
 
> For what is the 8pin power connector?  --  I have never seen it

Don't know.  Don't want to open my box while I writing email to look.
What does the ATX speck on Wikipedia say?

> 
> > One PCIe 6 pin connector is on bus 1, the other PCIe 6 pin connector is
> > on bus 3 (these are for one or two video cards that need the extra
> > power)
> 
> OK
> 
> > SATA conectors are on 12V bus 1
> > 
> > PATA drive connectors are also on 12V bus 1
> > 
> > All of these connectors use 18 AWG wire.
> > 
> > Floppy connector 12V is also on bus 1 but uses 22 AWG wire.
> 
> Hmmm, for example, can this work:
> 
> ATX-Connector   +12  V   3.3A   = RECOM RP40-2412SE
> + 5  V   8  A   = RECOM RP40-2405SE
> + 3.3V  12  A   = RECOM RP40-2403SE
> + 5  Vsb 2  A   = RECOM PP10-2405SEW
> - 5  V   0.3A   = RECOM ???
> -12  V   0.8A   = RECOM ???


IIRC, there's a single-chip solution for the -5 and -12V that comes in a
TO-220 package (looks like a normal 1A regulator), one pin regulated +5
(or +12V) in, centre pin common (connected to heat-sink), third pin is
-5V (or -12V) output.  I know its linear but it doesn't really matter
for 0.3A and 0.8A.  IIRC, they were made by TI.  

I needed these when I designed and built my own computer back in 1986.
It had 8 Zilog Z-80 8MHz CPUs with an 8-phase clock running at 64 MHz.
Everything was TTL includ

Re: [OT] ATX-PSU and amperage on connectors...

[Michelle Konzack]

Hi Douglas, 

its me again...  :-)


Am 2008-02-22 11:51:59, schrieb Douglas A. Tutty:
> DC output PeakContinuity  Max Power
> =
> +3.3 V25A 20A }
>   } 166 W
> + 5 V 25A 20A } 
> -
> +12V (bus 1)  19.5A   16A }
> +12V (bus 2)  19.5A   14A } 465 W
> +12V (bus 3)  19 A8A  }
> -
> -12V  0.8A0.5A  6W
> -
> 5Vsb  3.5A3.0A  15W
> =
> 
> 
> So the only trick for your design is what plugs from the PSU are on
> which 12V bus.  Here's the breakdown:
> 
> Motherboard connector, 12V is from bus 1.
> 
> 4-pin 12V power connector is on bus 2
> 
> 8 pin 12V power connector: pins 1 & 2 are from bus 1, pins 3 & 4 from
> bus 2.
> 
> One PCIe 6 pin connector is on bus 1, the other PCIe 6 pin connector is
> on bus 3 (these are for one or two video cards that need the extra
> power)
> 
> SATA conectors are on 12V bus 1
> 
> PATA drive connectors are also on 12V bus 1
> 
> All of these connectors use 18 AWG wire.
> 
> Floppy connector 12V is also on bus 1 but uses 22 AWG wire.
> 
> ---
> 
> Analysis:
> 
> Bus 1: 16A continuous, 19.5 A peak, is used for the MB connector, half
> of the 8-pin connector, one PCIe video connector, and all the drives.

OK, since ePCI2 is on Bus 3 and has 8A, stay 8A here too. The I asume, 
you have one double SATA cable and ond double PATA cable for together 4
devices which are arround 3A together.

This mean we have ~5A for the Mainboard and the 8pin connector from
which I do not know, for what it is.

Hmm, my ATX-Connector has only 1 yellow 12V cable, so it can not be very
much amperes...

...but 4 red 5V cables which mean, I need for 4 SATA/PATA drives at 
least 4A (DVD-Rom or DVD-Burner eating at least twice the energie as a 
HDD) and it we have 16A om 5V for the MB, 8pin and ePCI

> Bus 2: 14A continuous, 19.5 A peak, is used for half of the 8-pin
> connector and the 4-pin connector

Never had a P4 and never used a 8pin connector, so Bus 2 is wasted...

> Bus 3: 8A continuous, 19A peak, is used for one PCI-e connector.

Hmmm have no second ePCI (not even a first one :-)

> Given the design of this PSU, I can't say how much amperage goes, e.g.
> only to the MB or for each drive.  However, look at it this way.
> 
> Bus 3 is 8A is only goes to one PCI-e.
> 
> Bus 1 is 16 a and does most things including a PCI-e so if you figure
> that a PCI-e is 8A that leaves 8A for the MB and half the 8-pin
> connector, and all the drives.


Thanks, Greetings and nice Day
Michelle Konzack


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Re: [OT] ATX-PSU and amperage on connectors...

[Michelle Konzack]

Am 2008-02-22 11:51:59, schrieb Douglas A. Tutty:
> Hi Michelle
> 
> First,  you do know that one can purcase DC ATX PSUs?

Yes but with an efficienci horible...  40-70% only...

I am working with chips from Dallas, Maxim, NXP and LM and get over 85%.
And of cources, if you need a Vin of 24V (18-32V) you are lost.

> Second,  the individual drives don't take much power so I think the wire
> size is for mechanical support, I wouldn't go with less than 18 AWG.

I am not realy sure about this since I have for example:

+5   V +12   V
CD-Rom  noname   0.35A   1.7 A
CD-Rom  Teac CD-512E 1.5 A   1.3 A
CD-Rom  Teac CDR-55S 1.8 A   1.8 A

DVD-Rom AsusTek E616A1.5 A   1.5 A

HDD IDE IBM DHEA-38451   0.32A   0.26A
HDD SCSIIBM DDRS-39130   0.55A   0.65A
HDD SCSIIBM DDRS-34560   0.55A   0.65A
HDD SATA2   Hitachi HDT725032VLA360  0.73A   0.64A

Iomega ZIP 100   0.8 A


So if I take only the AsusTek DVD and the SATA2 disk which are two of
the latest models, then the 4pin HDD connector need already 

12V 2.22A   =  26.64 Watt
 5V 2.14A   =  10.70 Watt
  ---
   37.14 Watt

And if I see my "Enhance Electronics Co. Ltd" 300Watt PSU which has

 20pin  ATX connector
  6pin  ePCI connector
  4pin  P4 connector
  2 cables  with three HDD connectors
  1 cable   with two HDD and one Floppy connector

+ 3.3V  28  A \ 180 Watt \
+ 5  V  30  A /  | 279 Watt
+12  V  15  A/

+ 5  Vsb 2  A
-12  V   0.8A
- 5  V   0.3A

one of my problems is, that most DC-DC-Step-Down-regulators do not
support High-Voltage entry and most are limited to 14-16 Vin.

This mean, I need some High-Power (>=25A) DC-DC Step-Down regulators to
get 12Vout from 18-30Vin and then I can build the +5V and +3.3V from it.

> I'll give you the informaition from my ATX PSU's manual:

I have a list of over 50 ATX-PSU's too, but I need real values from the
Mainboards...

> So the only trick for your design is what plugs from the PSU are on
> which 12V bus.  Here's the breakdown:
> 
> Motherboard connector, 12V is from bus 1.
> 
> 4-pin 12V power connector is on bus 2
> 
> 8 pin 12V power connector: pins 1 & 2 are from bus 1, pins 3 & 4 from
> bus 2.

For what is the 8pin power connector?  --  I have never seen it

> One PCIe 6 pin connector is on bus 1, the other PCIe 6 pin connector is
> on bus 3 (these are for one or two video cards that need the extra
> power)

OK

> SATA conectors are on 12V bus 1
> 
> PATA drive connectors are also on 12V bus 1
> 
> All of these connectors use 18 AWG wire.
> 
> Floppy connector 12V is also on bus 1 but uses 22 AWG wire.

Hmmm, for example, can this work:

ATX-Connector   +12  V   3.3A   = RECOM RP40-2412SE
+ 5  V   8  A   = RECOM RP40-2405SE
+ 3.3V  12  A   = RECOM RP40-2403SE
+ 5  Vsb 2  A   = RECOM PP10-2405SEW
- 5  V   0.3A   = RECOM ???
-12  V   0.8A   = RECOM ???

Which mean, on each of +12V, +5V +3.3V I have a maximum of 40Watt
independant which will definitivly work for a 32-Bit Socket A CPU
from Duron over Sempron to Athlon up to 2000 MHz

My Workstation is a Sempron 2200+ (1500Mhz) with 1 GByte of memory
and is working fine with it, but switching to an Athlon 3000+ kill
the PSU (no, not the 3.3V but the 5V).

> Given the design of this PSU, I can't say how much amperage goes, e.g.
> only to the MB or for each drive.  However, look at it this way.

This what I am looking for.

Maybe I will make a 24pin-ATX-Adaper in which I put ANALOG Ampermeters.

The problem is, taht some CPU's are sucking realy 90 Watt alone...

> I suppose the question is how much of a computer do you intend to power
> on solar power?  Do you need a video card that requires a PCI-e?  How

Definitivly not.

> many drives do you want to be powering?  I don't want to open up my box

On my Workstation I am testing a IDE/CF-Adapter with a 4 GByte SanDisk
UltraII but I think I will switch to a cheaper 2 GByte one since I have
no KDE/GNOME On-Board.  /tmp and /var is in a ramdisk where the later
one is saved and restored from an init script at boot and shutdown
to/from a second CF-Card of 512 MByte as TAR-Archive which works perfectly.

On my Test-Server I have curently the 3W8500S-8LP with three normal SATA
Hitachi TravelStar 80 GByte (smaler where not availlable) in a Raid-1 plus
Hotfix and each drive has ONLY 5V/1.3A.

Now I like to install four Hitachi TravelStar from the E5K or E7K series
which allow 24/7 use on load...  it seems, the consuming 5V/1.4A.


One thing I do not know is, can the "normal" 80 GByte SATA TravelStar be
used 24/7 if there is only the OS on it and more or less N

Re: [OT] ATX-PSU and amperage on connectors...

[Henrique de Moraes Holschuh]

On Thu, 21 Feb 2008, Michelle Konzack wrote:
> I am designing (with the help of Dallas/Maxim, NXP and LM) new DC-ATX-
> PSU's (with 24V DC entry to use it in Photopholtaik-Systems) and was
> searching for the amperage of the connectors of an ATX-PSU.

Well, I recommend you go to extreme levels of output harmonics filtering,
that alone will increase system stability a damn great deal.  Some tests
using memory bit-rot testing a few years go (either by Ars Technica, or
Tom's, I don't recall) nicely illustrated why one would want to do so.

And don't think for a single moment that you are designing for linear loads.
Computers are [EMAIL PROTECTED]@[EMAIL PROTECTED] unhelpful loads, and the more 
efficient the
power-saving features in use in a system, the worse its load profile is when
it comes to harmonics.

> Does anyone know, where I can get the specifications for it?

Yes.  http://en.wikipedia.org/wiki/ATX, look at the external links section.

> and what about the SATA and old HDD connectors?

Look for the SATA and PATA specifications, they are not ATX-related.

> How many ampers must a cable support?

Cable choice depends on cable length, and acceptable voltage drop at given
load levels.  And you need to factor in in-rush and start current too if
they are non-trivial (and they are non-trivial for disks, fans, and anything
with high-drain CPUs or huge ammounts of RAM).

> If you want to ask why I need more or less exact values I respond:

If you play the el-cheap-o game with the cables and electronics, you will
get "nice" surprises when your systems face their first thermal challenge on
the form of an unusual hot (or cool) day.

-- 
  "One disk to rule them all, One disk to find them. One disk to bring
  them all and in the darkness grind them. In the Land of Redmond
  where the shadows lie." -- The Silicon Valley Tarot
  Henrique Holschuh


-- 
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with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]

Re: [OT] ATX-PSU and amperage on connectors...

[Douglas A. Tutty]

On Thu, Feb 21, 2008 at 07:31:45PM +0100, Michelle Konzack wrote:
> I am designing (with the help of Dallas/Maxim, NXP and LM) new DC-ATX-
> PSU's (with 24V DC entry to use it in Photopholtaik-Systems) and was
> searching for the amperage of the connectors of an ATX-PSU.
> 
> Does anyone know, where I can get the specifications for it?
> 
> E.g. the 24-pin ATX-Connector (24 pins) where we have
> 
> or  bl  bk  gn  bk  bk  bk  wt  rd  rd  rd  bl
> +---+
>++---+-+--+
>|O   O   O   O   O   O   O   O   O   O | O   O|
>|O   O   O   O   O   O   O   O   O   O | O   O|
>+--+--+
> or  or  bk  rd  bk  rd  bk  gr  pu  ye  ye  or
> 
> +12  V ye  yellow   =>  ???
> + 5  V rd  red  =>  ???
> + 3.3V or  orange   =>  ???
> + 5  Vsb   pu  purple   =>  2  A
> - 5  V wt  white  =>  1  A
> -12  V bl  blue =>  0,8A
>bk  black  =>  GND
> 
> same for the P4 connector (4 pins)
> +12  V ye  yellow =>  ???
> 
> the 6 pin ??? conector
> 
> bk  bk  bk  or  or  rd
> +---+
>++---++
>|O   O   O   O   O   O|
>+-+
> 
> + 5  V rd  red  =>  ???
> + 3.3V or  orange   =>  ???
> 
> and what about the SATA and old HDD connectors?
> How many ampers must a cable support?
> 
> If you want to ask why I need more or less exact values I respond:
> 
> I have the need for 38 DC-PSU's for my own for a solar powered Project
> and since my money is very limited, I want to avoid to buy electronics
> I do not need...
> 
> Also I like to make the DC-PSU modulable, which mean, a standard layout
> for the ATX-Connector and then modules which can be added if needed for
> P4 conector, 6-Pin-XXX conector or the HDD connectors.  Also I want to
> use ISO or AMP connectors insteed of making fixed cables on the DC-PSU
> which bother me (personaly) if not needed.
> 
> For example, I was planing to use DC-DC-Converters from RECOM which have
> a very high efficiency (>=88%) but are non realisable since a 40 Watt
> model cost arround 72 Euros which mean for the ATX connector:
> 
> +12  V  =>  3,3A   40W  70 Euro
> + 5  V  =>  8  A   40W  70 Euro
> + 3.3V  => 12  A   40W  70 Euro
> + 5  Vsb=>  2  A   10W  25 Euro
> - 5  V  =>  1  A5W  15 Euro
> -12  V  =>  0.8A   10W  25 Euro
> ---
>145W275 Euro
> 
> and a HDD-Cable for three/four devices could be something like
> 
> +12  V  =>  3,3A   40W  70 Euro
> + 5  V  =>  3  A   15W  30 Euro
> ---
>55W 100 Euro
> 
> So I can forget this nice DC-DC converters which simplyfiy design by
> factor 20 but of the costs...
> 
> Even if I buy produce 1000 PSU's the price would be over 300 Euro
> complete per unit.  (The "PicoPSU", a PSU on a ATX connector, support
> only 12Vin but provides 120 Watt and costs arround 100 Euro)
> 
> Dallas, Maxim, NXP and LM offer step-Down regulators in 4x4mm to 6x6mm
> cases with 3.3V, 5V, 12V plus negativ voltages up to 60 Ampere for
> 0.68 US$ to 3.27 US$
> 
> And yes, I have already tonns of free samples laying around in my
> appartement...  (nice to solder TQFN packages... :-)
> 
Hi Michelle

First,  you do know that one can purcase DC ATX PSUs?

Second,  the individual drives don't take much power so I think the wire
size is for mechanical support, I wouldn't go with less than 18 AWG.

I'll give you the informaition from my ATX PSU's manual:

Cooler Master iGreen Power 600W User Manual.

Double Forward Switching Circuit for 85% efficiency

Compliant with Intel Standard ATX 12V V 2.2.
Compliant with  SSI standard EPS 12V v 2.91


Output specs:

DC output   PeakContinuity  Max Power
=
+3.3 V  25A 20A }
} 166 W
+ 5 V   25A 20A } 
-
+12V (bus 1)19.5A   16A }
+12V (bus 2)19.5A   14A } 465 W
+12V (bus 3)19 A8A  }
-
-12V0.8A0.5A  6W
-
5Vsb3.5A3.0A  15W
=


So the only trick for your design is what plugs from the PSU are on
which 12V bus.  Here's the breakdown:

Motherboard connector, 12V is from bus 1.

4-pin 12V power connector is on bus 2

8 pin 12V power connector: pins 1 & 2 are from bus 1, pins 3 & 4 from
bus 2.

One PCIe 6 pin connector is on bus 1, the other