MOTM

> From: Paul Schreiber <synth1@...>
> 2) If you are planning a cabinet that holds over 22 MOTM
> modules, then I *strongly* suggest getting a larger supply.
> I suggest the Power One model HBB15-1.5-A. It is 1"
> larger in all 3 dimensions, but can power twice as
> many modules.

> Available from Newark, Allied, etc. Surplus ones pop-up
> here and there as well.

Ditto.  I have three of the Power one supplies, two of which are the one
Paul lists above  Several of us have purchased these supplies surplus for
$20 each.

> 3) If you plan to use multiple 900PCB boards in a system, the
  *best way* is to run 16ga. wire from *each* board back to
   the Power One. They way *I* would do it is get a "barrier strip"
   and connect the Power One to it. Then, run wires from the
   900PCBs to the strip. *I* would use crimp terminals like what
   comes with the wire set in the MOTM-900. These terminals
   are at any hardware store. Crimping tools are cheap, too (like $6).

This is exactly how I do mine, barrier strip and all.  I have offered before
and will offer again to send FREE case-size lengths of 14 guage utility
grade wire to any MOTMer for this use.  We use MILES of this stuff at work,
and pieces 10-15 foot are simply trash at work, but great for home.  When
wiring control panels at work, our wiremen do crimp everything.  At home, I
solder the wire in the terminals (anal-retentive stooge stuff).

For those that are truly anal-retentive and want to have a MOATS (mother of
all terminal strips).  I occasionally get my hands on these used too.  They
are not your Radio Shack stuff, but are about 2" X 8" with 10 terminal on
each side.  We use them at work for 130 volts DC and they have about a # 10
screw that even "Larry the mad torquer" could not strip out.

Larry Hendry

In a message dated 8/5/2000 8:14:13 PM, synth1@... writes:

>2) If you are planning a cabinet that holds over 22 MOTM modules, then
>I
>*strongly* suggest getting a larger supply. I suggest the Power One model
>HBB15-1.5-A. It is 1" larger in all 3 dimensions, but can power twice as
>many
>modules.

This is the PSU I've been using. I was able to mount it to the 900 front 
panel by merely (very carefully) drilling two mounting holes through the 
PSU's brushed aluminum body. It's a bit of a tight fit, but it will work.

BTW, do the power consumption figures which indicate optimal power 
consumption remain roughly constant regardless of what the modules is doing 
(i.e., is a VCO in a static drone state using similar amounts of power to one 
which is being modulated by all sorts of external modules)?

JB

how would one integrate a new power supply such as the one below with an 
existing motm-900 in such a way as that the switch on the existing 900 
turns on both the new Power One and the existing 900?

mark

At 04:56 PM 8/6/00 -0400, you wrote:

>In a message dated 8/5/2000 8:14:13 PM, synth1@... writes:
>
> >2) If you are planning a cabinet that holds over 22 MOTM modules, then
> >I
> >*strongly* suggest getting a larger supply. I suggest the Power One model
> >HBB15-1.5-A. It is 1" larger in all 3 dimensions, but can power twice as
> >many
> >modules.
>
>This is the PSU I've been using. I was able to mount it to the 900 front
>panel by merely (very carefully) drilling two mounting holes through the
>PSU's brushed aluminum body. It's a bit of a tight fit, but it will work.

In a message dated 8/6/2000 5:57:36 PM, n0nspaz@... writes:

>how would one integrate a new power supply such as the one below with an
>existing motm-900 in such a way as that the switch on the existing 900
>turns on both the new Power One and the existing 900?

Larry had a great idea (if one of the 900s was enclosed with a different 
front panel) using a female IEC connector and wiring the AC of one module so 
that one 900 turned on both PSUs.

Maybe Larry has thought about this more and can let us in on what he's found?
JB

----- Original Message -----
> From: <jwbarlow@...>
> Larry had a great idea (if one of the 900s was enclosed
> with a different front panel) using a female IEC connector
> and wiring the AC of one module so that one 900 turned
> on both PSUs.

Well, that was a slightly different discussion on a nice way to possibly
integrate multiple 900s.  However, since I don't own a 900 and have the 900
docs, I can't really give informed advice.

> I remember Gene Stopp on the diy list suggesting that it was
> well worth it to run PSUs at about 50% of their rating.

I can offer my opinion in this.  I think that approach is a bit
conservative.  However, leaving head room is a good idea.  I plan to load my
supplies based more on how many modules are in "that" particular cabinet.
However, in all cases, I will probably draw the line at about 80% of
nameplate.

As a point of interest, I would like to point out how your local power
company determines the loadability of transformers and power lines.  The
"nameplates" are just guidelines.  The industry standard is to operate the
transformer up to the maximum load that will not get the transformer any
hotter than XXX degrees C.  Everybody uses different numbers for that limit,
but it is ALWAYS well above the nameplate.  Power line loading is based on
sag in the wire (no sh*t).  The loadabiliy of the line is based on the
physical clearance between the wire and whatever is below it (or the
clearance to ground code).  Normally, that is in the 80 to 100 degrees C
range.

Disclaimer:  Do not use these methods at home.  We are trained
professionals.  :)

Larry (I often refer to 12.5 KV as the "low voltage" stuff) Hendry