Dead mini-ITX PSU

[D.M. Procida]

The PSU in my mini-ITX box seems to have died.

It's this PSU, as far as I can tell:
<http://www.itx-warehouse.co.uk/Product.aspx?ProductID=435> (it
certainly looks like that).

There's no internal fuse that I can identify, and though there's a
generic-looking warning inside about only replacing the fuse with one of
the same rating, there's no mention of a fuse on the label.

I can't see any blown capacitors in there either, but there's nothing
coming out of it at all.

I think the PSU is discontinued, which means that the whole box is
pretty much useless.

Annoying - I was going to give it away, but I'd hate to throw it away.
It was happily runnng an ancient iMac motherboard inside there.

I don't know much about computer PSUs, but I take it that the chances of
getting hold of a compatible replacement is slim?

Daniele

[The Natural Philosopher]

no, id say its quite high.


Got a vast rackmount case and PSU somewhere as well..


A mini ITX case complete with PSU is not that much more expensive either.



> Daniele


--
To people who know nothing, anything is possible.
To people who know too much, it is a sad fact
that they know how little is really possible -
and how hard it is to achieve it.

[Theo Markettos]

D.M. Procida <real-not-anti...@apple-juice.co.uk> wrote:
> I don't know much about computer PSUs, but I take it that the chances of
> getting hold of a compatible replacement is slim?

Electrically, there's plenty or similar or higher wattage that would do the
job. So it's just a case of finding something of the right physical size
with sufficient connectors for what you need. The web page doesn't give
dimensions, but you can fit something of the same power but smaller (which
do exist) if you can find a way to mount it in the case.

Theo

[Dave Liquorice]

On Wed, 13 Jun 2012 16:16:27 +0100, D.M. Procida wrote:

> It's this PSU, as far as I can tell:
> <http://www.itx-warehouse.co.uk/Product.aspx?ProductID=435> (it
> certainly looks like that).

That one has a 110/240v switch rather than auto switching. Maybe if
yours has a similar switch it has got knocked or full of dust,
checkit give it a waggle?

> I don't know much about computer PSUs, but I take it that the chances of
> getting hold of a compatible replacement is slim?

Unless it's *very* ancient and I wouldn't call mini-ITX very ancient
or the case very strange you probably can get a replacement. PC parts
are pretty much standardised in location of mounting holes fans etc.

--
Cheers
Dave.

[Graham.]

On Wed, 13 Jun 2012 16:16:27 +0100,

There will be a fuse on the PCB, It is often wire ended and soldered
in.

Unscrew the PCB from the chassis so you can get to the underside.
Using a meter on low ohms or continuity beeper range, trace where the
live pin of the IEC connector goes. It shoud go to the fuse and then
via interference suppression choke winding to the AC side of a bridge
rectifier.
The neutral side will do much the same without the fuse. The DC output
of the bridge goes to a pair of 200 volt electrolytes that are in
series when the voltage selector is set at 230v. These are the caps
that people warn you to discharge.

After that it gets more complex, but the input circutry of any
switchmode PSU really is as simple as I have described and it's well
worth doing some cold tests.



--
Graham.
%Profound_observation%

[Bernard Peek]

On 13/06/12 16:16, D.M. Procida wrote:

>
> I don't know much about computer PSUs, but I take it that the chances of
> getting hold of a compatible replacement is slim?

ITX warehouse have possible replacements. A 12v power brick together
with an adapter that plugs into the motherboard's 20/24-pin power socket.



--
Bernard Peek
b...@shrdlu.com

[John Rumm]

On 13/06/2012 16:16, D.M. Procida wrote:
> The PSU in my mini-ITX box seems to have died.
>
> It's this PSU, as far as I can tell:
> <http://www.itx-warehouse.co.uk/Product.aspx?ProductID=435> (it
> certainly looks like that).
>
> There's no internal fuse that I can identify, and though there's a
> generic-looking warning inside about only replacing the fuse with one of
> the same rating, there's no mention of a fuse on the label.
>
> I can't see any blown capacitors in there either, but there's nothing
> coming out of it at all.


> I think the PSU is discontinued, which means that the whole box is
> pretty much useless.

I have a Ideq small form factor machine here that I was probably going
to scrap - the PSU on that may well fit in your case. If you measure the
dimensions of yours, I can let you know if it will fit.

> Annoying - I was going to give it away, but I'd hate to throw it away.
> It was happily runnng an ancient iMac motherboard inside there.

As a check, to make sure it really is the PSU, disconnect it from the
motherboard, and force it to startup on its own by briefly connecting
the green wire in the motherboard connector to one of the black wires
using a offcut of wire etc.

> I don't know much about computer PSUs, but I take it that the chances of
> getting hold of a compatible replacement is slim?

Reasonably good I would have thought.

--
Cheers,

John.

/=================================================================\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\=================================================================/

[D.M. Procida]

Graham. <m...@privacy.net> wrote:

> >There's no internal fuse that I can identify, and though there's a
> >generic-looking warning inside about only replacing the fuse with one of
> >the same rating, there's no mention of a fuse on the label.

> There will be a fuse on the PCB, It is often wire ended and soldered
> in.

You were right! There is a cunningly-placed vertical fuse, sheathed in
heat-shrink plastic. Weirdly, the fuse seems to rotate on its axis, so I
don't know what kind of fitting it has.

Sadly (or not) the fuse hasn't blown; there's continuity across it, so
that doesn't appear to be the issue.

> Unscrew the PCB from the chassis so you can get to the underside.
> Using a meter on low ohms or continuity beeper range, trace where the
> live pin of the IEC connector goes. It shoud go to the fuse and then
> via interference suppression choke winding to the AC side of a bridge
> rectifier.
> The neutral side will do much the same without the fuse. The DC output
> of the bridge goes to a pair of 200 volt electrolytes that are in
> series when the voltage selector is set at 230v. These are the caps
> that people warn you to discharge.

I shouldn't expect to find DC continuity across the bridge, should I?

Daniele

[D.M. Procida]

John Rumm <see.my.s...@nowhere.null> wrote:

> > I think the PSU is discontinued, which means that the whole box is
> > pretty much useless.
>
> I have a Ideq small form factor machine here that I was probably going
> to scrap - the PSU on that may well fit in your case. If you measure the
> dimensions of yours, I can let you know if it will fit.

That's kind. The specs are:

Internal Switching Power Supply:
Model No.: ENP-2222D
Dimensions: (mm) 150 (L) x 82 (w) x 65 (H)
Intput : 200-240V~ / 3A 50Hz
Output : +3.3V 17A
+5V 13A
+12V 16A
-5V 0.3A
-12V 0.3A
+5V 2A
Total : 220.00W

But it's a slightly odd a shape - as in:
<http://www.itx-warehouse.co.uk/Product.aspx?ProductID=435>.

Daniele

[Bob Eager]

That doesn't look like a 'standard' Mini-ITX PSU, unfortunately.

I'd go for a pico-PSU and an external power brick. Easy fix for Daniele,
I would hope!



--
Use the BIG mirror service in the UK:
http://www.mirrorservice.org

*lightning protection* - a w_tom conductor

[Bob Eager]

I suggested that too, but a lot of those are limited in what they can
deliver. Depends on the drives, etc. although the Morex cases generally
only support laptop-style optical drives and one hard drive.

[Graham.]

No. Your meter will have a diode test range and the reading is
actually in volts. Across any adjacent pins on the bridge rectifier
you will see a reading in the order of 0.6v in one direction and
considerably higher in the other.

But as the fuse is intact I don't think that will be your problem, as
if any diode(s) in the bridge went short circuit it would take out the
fuse, (or the printed track connecting it).

Is there a low resistance connection from the middle two pins of the
bridge to the L & N pins of the IEC mains socket?

--
Graham.
%Profound_observation%

[John Rumm]

On 13/06/2012 20:12, D.M. Procida wrote:
> John Rumm<see.my.s...@nowhere.null> wrote:
>
>>> I think the PSU is discontinued, which means that the whole box is
>>> pretty much useless.
>>
>> I have a Ideq small form factor machine here that I was probably going
>> to scrap - the PSU on that may well fit in your case. If you measure the
>> dimensions of yours, I can let you know if it will fit.
>
> That's kind. The specs are:
>
> Internal Switching Power Supply:
> Model No.: ENP-2222D
> Dimensions: (mm) 150 (L) x 82 (w) x 65 (H)

approx 142 x 80 x 55

> Intput : 200-240V~ / 3A 50Hz
> Output : +3.3V 17A
> +5V 13A
> +12V 16A
> -5V 0.3A
> -12V 0.3A
> +5V 2A

Yup - same spec...

> But it's a slightly odd a shape - as in:
> <http://www.itx-warehouse.co.uk/Product.aspx?ProductID=435>.

This one is a more regular cuboid - but a tad smaller as above

[Johann Klammer]

D.M. Procida wrote:
> The PSU in my mini-ITX box seems to have died.

How did you test it?
Did you plug in a different PSU?
If you do an offline test, you have to pull the PS_ON pin(14) low
briefly to turn it on. But 5V standby(9) should be available as soon as
plugged in. Pinout: http://www.hardwarebook.info/ATX_Power_Supply
If the whole box just does not work anymore, it may as well be the
mainboard.

[D.M. Procida]

Graham. <m...@privacy.net> wrote:

> No. Your meter will have a diode test range and the reading is
> actually in volts. Across any adjacent pins on the bridge rectifier
> you will see a reading in the order of 0.6v in one direction and
> considerably higher in the other.

It's part of the resistance range, and shows around 670 (Ohms, I
presumed) in one direction, and an open circuit in the other.

This is across any two pins, except the two in the middle (the rectifier
is a square block, not discrete components).

> But as the fuse is intact I don't think that will be your problem, as
> if any diode(s) in the bridge went short circuit it would take out the
> fuse, (or the printed track connecting it).
>
> Is there a low resistance connection from the middle two pins of the
> bridge to the L & N pins of the IEC mains socket?

In one direction only, and it's about 2 Ohms for one pin and about 10 in
the other.

I actually picked up a second hand signal generator and oscilloscope
recently - would they be useful in this?

Daniele

[Jules Richardson]

On Thu, 14 Jun 2012 15:04:01 +0100, D.M. Procida wrote:
> I actually picked up a second hand signal generator and oscilloscope
> recently - would they be useful in this?

If you're serious about fixing it, then the following is a useful
resource: http://www.repairfaq.org/sam/smpsfaq.htm

I think that a meter's normally all you need though when it comes to
completely dead PSUs; something will likely test as shorted or open when
it shouldn't be etc.

Think about the simple stuff first - Does the fan run? Does it twitch at
all when the machine's powered up? Do you get any voltage at all on the
various outputs? Are you sure that the machine's power button (and
related wires) are OK? Are you sure that the motherboard isn't toast (and
the PSU is seeing a short circuit and shutting down)?

cheers

Jules

[D.M. Procida]

John Rumm <see.my.s...@nowhere.null> wrote:

> Yup - same spec...
>
> > But it's a slightly odd a shape - as in:
> > <http://www.itx-warehouse.co.uk/Product.aspx?ProductID=435>.
>
> This one is a more regular cuboid - but a tad smaller as above

Does yours have a model number on it, so I can compare the mounting
points etc?

Thanks,

Daniele

[avant...@googlemail.com]

Hi

A very good place is Avanti Power Repairs Ltd
Call them on 01189-820 911

They fix all types of power supplies

[avant...@googlemail.com]

Hi a good company to try is Avanti Power Repairs Ltd

They will look at your unit free of charge before coming back to let you know if they can repair it. Call them on 01189-820 911. www.avantipr.co.uk

[The Other John]

Not a very good place if they can't even spot the original post
is over 2 years old!

--

TOJ.

[Brian Gaff]

Yes I was just thinking the same. Maybe its like that mythical village in
that book which I forgot the title of?


Brian

--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email: bri...@blueyonder.co.uk
______________________________________________________________________________________________________________


"The Other John" <nom...@home.org> wrote in message
news:DenJv.39929$_u1....@fx30.am4...

[Graham.]

On Thu, 21 Aug 2014 14:20:19 GMT, The Other John <nom...@home.org>
wrote:

(s)he also doesn't know how to format a Reading phone number. The STD
code is 0118 the 9 is part of the local number.



--

Graham.

%Profound_observation%

[Bob Eager]

It's a 'he'. Ex-student of mine as it happens.

Didn't see the original (2 year old) post but ordinary mini ITX suppplies
are easy to find. Or use one of the nano PSUs and a 12 volt brick.



--
My posts are my copyright and if @diy_forums or Home Owners' Hub
wish to copy them they can pay me £30a message.

Use the BIG mirror service in the UK: http://www.mirrorservice.org

*lightning surge protection* - a w_tom conductor

[Grimly Curmudgeon]

On Thu, 21 Aug 2014 06:37:14 -0700 (PDT), avant...@googlemail.com
wrote:

>Hi a good company to try is Avantool Spamming Arsehole Power Repairs Ltd

Fuck off, there's a good chap.