MOTM

At 7:53 PM +0100 04/01/01, Hugo Haesaert wrote:
>Hi All !
>
>There are locking DIN connectors that have a different pin out than
>the MIDI ones .  Should be a bit cheaper than the xlr's .

They are much cheaper, but DIN can't be connected to an 18AWG wire, and
certainly not 14AWG.

At 1:42 PM -0500 04/01/01, J. Larry Hendry wrote:
>
>Well, the best connection for each module is directly to the power supply
>>in a star type fashion.  However, when you get your system up to the 40 +
>module range, this is not practical.  So, I put the PCBs closer to the
>modules they serve and run the larger wire to the PCBs.  So the current of
>all 12 modules served from that PCB is on the wiring to the power supply.
>OK, so whats the big deal?  It might be 400 mA or so per PCB.  The wire is
>not sized to the current flow expected.  If it were, # 18 would be
>>oversized for everythying.

Good point, but have you seen the size of rest of the system?? :)

>It is sized to eliminate small voltage drops between the
>power supply and the distribution  PCB.  These unwanted voltage drops cause
>by current draw variations in one module can cause interation with another
>module.

Hmmmm...

>You are comparing apples to oranges. The voltage drop in these AC lines
>really has no negative effect on your gear.  Small voltage fluctuations on
>your 15 VDC line do.  The AC supply voltage at your main panel routinely
>varies by as much as 3 or 4 volts (more in California) even before
>variations caused by voltage drop is considered.  We (power companies, my
>vocation) vary the AC voltage delivered to your house on purpose.  US code
>specifies anything between 114 and 126 as acceptable for residential
>service.

This is true, and that's before it's regulated twice.

>4 conductor is getting more common.  New code is requiring a
>ground separate from neutral now on many 240 volt appliances (UL
>caught on to the fact that these appliances have 120 volt connections.

Most of the ones I've seen have been solid, not stranded.

>The official MOTM power jumper PCB with 12 MTA156-4 connectors is
>2 1/2" x 4 3/16" by my measurement. I can send you a photo of one if you
>>like.

Thanx!!  A measurement is exactly what I needed.  Although I don't think a
photo is necessary.  Now I have to go measure an outlet box.

>Oh, I forgot to tell you.  You ony run three wires fromt he PCB to the
>power supply.  Paul made the grounds common at the PCB supply.
>So you only need 3 conductors between the power supply and the MOTM-900
>>PCB.  That's another good reason to keep the wire big.

Excellent!!!  I think I can find 14AWG/3 stranded without having to chop
down an extension cord (which isn't even an option with four conductors).

You have been very helpful.

THANX!!