Modular power...

[Tony Scharf]

Well, it gets more interesting with my PSU problem.

I did some troubleshooting today, and it seems that when the unit is
on its only drawing about 1a which is well within the normal operating
parameter of the PSU.  The problem is that on start up, this spikes
way up causing the PSU to think its overloaded and the PSU goes into
some kind of shut down mode as a safty feature.

I should add this only happens on a warm start.  On a completely cold
start, everything powers up normally.  My thought is (and I could be
very wrong) that the resistance is slightly higher in the colder
system, enough that it slows down the peek current draw allowing the
system to start up.  Once started, everything is fine...but if I power
down and install a module without letting it fully cool down (like I
did when I first noticed this problem) I get the start up peak
problem.

So...my question is this:  could it be cheaper to put in switches for
each buss board, so that I could manually delay their power up or is
there some kind of circuit I could install that would do this for me?
something I could put between the buss boards and the psu and set each
to a slightly different delay (probably a few milliseconds is all it
takes).  Or is this a completely unsafe thing to contemplate, and I
should just buy a new PSU as I had intended?

Tony

On Sat, May 7, 2011 at 4:32 PM, Tom Adam <tom.adam at thebigear.be> wrote:
> Have a look at the Power One PSU's.
> Power One #HBB15-1.5-A
> Power One #HCBB-75W-A (huge)
> They can give +/-12V or +/-15V.
> I've got two of each. Bought cheaply on Ebay. I like them since they
> don't make any sound. I hate buzzing transformers.
>
> You can easily measure the current yourself. I made a small pcb just for
> that. But be careful, I once blew up a couple of IC's by disconnecting
> the -Ve rail when measuring.
>
> And if you're not sure any more of the PSU, buy a new one. It is the
> hart of your modular, consider the damage when it really blows up...
>
> Cheers,
> ToAd
>
> Op 7-5-2011 23:10, Tony Scharf schreef:
>> Yeah, It ran perfectly till today.  What really sucks is that about
>> half the moldules in my rig dont have their current draw in their
>> documentation (or documentation at all in some cases...).
>>
>> I can get things working, but only if I pull out more than I just put
>> in.  I think I may have blown something.
>>
>> I am going to look for a way to move the PSU external to the case, and
>> get something with some more beef to it than the stock (if thats
>> possible...this is not exactly my expertise).  Here is to hoping..
>>
>> Tony
>>
>> On Sat, May 7, 2011 at 3:32 PM, Tom Adam<tom.adam at thebigear.be>  wrote:
>>> They always told me you should only load the PSU for 70 to 80%. So
>>> driving it at the limit might not be a good idea.
>>> Check the SDIY archives for the tech talk.
>>>
>>> I have 4 Pro One PSU's in my modular. Load is between 45 and 80% and the
>>> thing seem to run perfectly.
>>>
>>> ToAd
>>> (Back to the bi annual calibration session of my modular)
>>>
>>>
>>> Op 7-5-2011 21:19, Tony Scharf schreef:
>>>> So I did what every noob does and bought more modules than his power
>>>> supply can handle.  Its rated at 1200mA and actually has been running
>>>> fine at 1300...but one module I bought pushed it over the top.
>>>>
>>>> Rather than shelling out for a new case right now, I was wondering how
>>>> much DIY work it would be to pull out the PSU I have, and connect up
>>>> something like an external 2000mA power supply to get the extra
>>>> headroom?  The case is almost full, and I am really only a little
>>>> short.  In my mind, it seems like it would be easy as taking out the
>>>> current PSU and wiring it in same as my old board. Of course, I could
>>>> be wrong...
>>>>
>>>> Tony
>>>>
>>> _______________________________________________
>>> music-bar mailing list
>>> music-bar at lists.music-bar.org
>>> http://lists.music-bar.org/cgi-bin/mailman/listinfo/music-bar
>>>
>>
>>
>
> _______________________________________________
> music-bar mailing list
> music-bar at lists.music-bar.org
> http://lists.music-bar.org/cgi-bin/mailman/listinfo/music-bar
>



-- 
---------------------------------------------------------------------
NoiseTheorem:
Facebook: http://www.facebook.com/NoiseTheorem
myspace:http://www.myspace.com/noisetheorem
soundcloud:http://soundcloud.com/noisetheorem