MOTM

My intent here is to (hopefully) motivate a comprehensive discussion that
will (hopefully) result in a set of guidelines about powering a motm based
system whose mA draw exceeds the ability of a single 900 [I'm not asking
too much am I :-)]. After spending about 2.5 h in the motm archives (and
several related sites) the topic is still somewhat vague to me [yes,
novice speaking].  However, I anticipate that my situation is not unique,
and at least will occur for others in the (near) future.  Please redirect
me if I've missed comprehensive coverage of this topic.


Situation:  I've reached a point where my mA draw of modules will soon
exceed the 'safe' (700mA: Paul S.) supply of my single 900.  So I am
looking at (as the character Tim Taylor is fond of saying) "more power".

(1) I could just add a second 900.  However, my future module space is
limited - 6 unit widths is real real estate.

(2) I've read the Power 1 suggestions (including Dave's very nice motm
parts page & Digikey):
(a)  Is there a single Power 1 supply that will power, say, > 50 modules
(or is this even sensible)?
(b) How is a Power 1 supply 'assembled' (ie., components required,
assembly required, mta module connections (motm 960, I suppose),
stand-alone housing,...)?  Here I am thinking of parts list and
 instructions, like an electronics kit approach.

(3) Paul S: Do you have any anticipated plans for a 3U power module with
"more power"?

If I"m asking too much please tell me.  However, I think that a 'motm
power supply resource' would help out a fair number of us, especially as
our motm systems continue to grow in the next several years
(realistic optimism).

Thanks, Jeff

I know what you mean about a nice PSU tutorial for our ever growing MOTM 
systems. My solution (which addresses your questions 2b and 3, in a way) was 
to use a larger Power One supply (I think the number is an HBB 15-1.5A) which 
supplies almost double the power of the MOTM 900. I was able to mount it on 
the 900 front panel with very little trouble -- I did have to drill new 
mounting holes in the aluminum frame of the Power One unit (being careful as 
to not drill too deep and accidentally drill into the transformer). I also 
had to be rather careful to locate the Power One unit in the right horizontal 
position since there is very little clearance on the sides with this wider 
unit. I can't imagine a larger unit than the HBB size being able to fit 
against a 3U FP -- of course you could always go case mounted.

I was able to use the MTA power block without any problems but I also added a 
barrier strip since I wanted many more PSU connections.

JB

In a message dated 4/15/2001 8:03:33 AM, jpont@... writes:

>(2) I've read the Power 1 suggestions (including Dave's very nice motm
>parts page & Digikey):
>(a)  Is there a single Power 1 supply that will power, say, > 50 modules
>(or is this even sensible)?
>(b) How is a Power 1 supply 'assembled' (ie., components required,
>assembly required, mta module connections (motm 960, I suppose),
>stand-alone housing,...)?  Here I am thinking of parts list and
> instructions, like an electronics kit approach.
>
>(3) Paul S: Do you have any anticipated plans for a 3U power module with
>"more power"?

If your modules are all in one cabinet and the larger power supply isn't big
enough you could always parallel two power supplies off of the MOTM 900
switch.

John Loffink
microtonal@...

----- Original Message -----
From: <jwbarlow@...>
To: <motm@yahoogroups.com>
Sent: Sunday, April 15, 2001 12:36 PM
Subject: Re: [motm] power supplies for growing motm system


> I know what you mean about a nice PSU tutorial for our ever growing MOTM
> systems. My solution (which addresses your questions 2b and 3, in a way)
was
> to use a larger Power One supply (I think the number is an HBB 15-1.5A)
which
> supplies almost double the power of the MOTM 900. I was able to mount it
on
> the 900 front panel with very little trouble -- I did have to drill new
> mounting holes in the aluminum frame of the Power One unit (being careful
as
> to not drill too deep and accidentally drill into the transformer). I also
> had to be rather careful to locate the Power One unit in the right
horizontal
> position since there is very little clearance on the sides with this wider
> unit. I can't imagine a larger unit than the HBB size being able to fit
> against a 3U FP -- of course you could always go case mounted.
>
> I was able to use the MTA power block without any problems but I also
added a

> barrier strip since I wanted many more PSU connections.
>
> JB
>
> In a message dated 4/15/2001 8:03:33 AM, jpont@... writes:
>
> >(2) I've read the Power 1 suggestions (including Dave's very nice motm
> >parts page & Digikey):
> >(a)  Is there a single Power 1 supply that will power, say, > 50 modules
> >(or is this even sensible)?
> >(b) How is a Power 1 supply 'assembled' (ie., components required,
> >assembly required, mta module connections (motm 960, I suppose),
> >stand-alone housing,...)?  Here I am thinking of parts list and
> > instructions, like an electronics kit approach.
> >

My thanks to JB, Dave, and John for their comments and detailed
instructions.  Some diverse options to think about.  Other comments are
certainly welcome.
Jeff