The Definitive Connecting Power Thread

Rex Coil 7 · Post by **Rex Coil 7** » Mon May 13, 2019 8:10 am

smetak wrote:Had the same exact problem with connecting the Polivoks a few months ago - yep, there are no markings and nothing in the manual - can't for the life of me understand why they they have to make this so friggin' hard! - the only way of doing it right is contacting them directly (not at home right now, so the module itself is out of reach and can't find their reply - must have deleted it by accident).

I remember that I was "almost certain" of the polarity, until I received a reply from them and found out I was completely amiss. So, DO NOT connect it before contacting them! Their reply is usually very prompt.

... then bust out the Sharpie and MARK that sumbitch!

smetak · Post by **smetak** » Mon May 13, 2019 9:04 am

Rex Coil 7 wrote:
smetak wrote:Had the same exact problem with connecting the Polivoks a few months ago - yep, there are no markings and nothing in the manual - can't for the life of me understand why they they have to make this so friggin' hard! - the only way of doing it right is contacting them directly (not at home right now, so the module itself is out of reach and can't find their reply - must have deleted it by accident).

I remember that I was "almost certain" of the polarity, until I received a reply from them and found out I was completely amiss. So, DO NOT connect it before contacting them! Their reply is usually very prompt.
... then bust out the Sharpie and MARK that sumbitch!

Yeah, that's the usual feeling I have when I encounter unmarked PCBs......pain in the arse!

luchog · Post by **luchog** » Mon May 13, 2019 6:54 pm

smetak wrote:Had the same exact problem with connecting the Polivoks a few months ago - yep, there are no markings and nothing in the manual - can't for the life of me understand why they they have to make this so friggin' hard! - the only way of doing it right is contacting them directly (not at home right now, so the module itself is out of reach and can't find their reply - must have deleted it by accident).

I've emailed them about this. Hopefully I'll hear back soon.

Rex Coil 7 wrote: ... then bust out the Sharpie and MARK that sumbitch!

Sharpie ain't a-gonna show up well on that black PCB mask. I'm busting out the red paint to mark this thing.

Rex Coil 7 · Post by **Rex Coil 7** » Mon May 13, 2019 9:44 pm

luchog wrote:
smetak wrote:Had the same exact problem with connecting the Polivoks a few months ago - yep, there are no markings and nothing in the manual - can't for the life of me understand why they they have to make this so friggin' hard! - the only way of doing it right is contacting them directly (not at home right now, so the module itself is out of reach and can't find their reply - must have deleted it by accident).
I've emailed them about this. Hopefully I'll hear back soon.

Rex Coil 7 wrote: ... then bust out the Sharpie and MARK that sumbitch!
Sharpie ain't a-gonna show up well on that black PCB mask. I'm busting out the red paint to mark this thing.

Silver Sharpie ....

charonme · Post by **charonme** » Tue May 14, 2019 3:08 am

cackland wrote:Does the module have diodes around the header area?

If so, there should be an indication of the polarity of those diodes. Depending on the diode, the indication varies (A line, a stroke etc) The diode with its indicator facing away from the header should be the +12v, and the the opposite for the -12V.

NO!!!, don't! :youkids:

this depends on where the other end of the diode is going!!! Some manufacturers use a protection schottky diode that is supposed to short the power source when plugged incorrectly, these have the diode anode connected to -12v input and cathode to +12v. Others use diodes connected in the power path that would prevent current flow if the power was plugged in incorrectly, one has its cathode connected to -12v and the other has its anode connected to +12v

I'd rather check where the power decoupling polarized capacitors are connected, usually +12v -> [+]cap[-] -> gnd -> [+]cap[-] -> -12v

also if you can see some common ICs on the board like tl074 or lm13700, find which pins are supposed to be connected to +V and -V in their datasheets and check it on the board with a continuity tester

sutekina bipu-on · Post by **sutekina bipu-on** » Fri Jun 14, 2019 5:45 am

What would you guys suggest if i was to make a 12U open frame rack like this with the necessary extra rails to mount euro? I'm trying to figure out the best way to deal with distributing power.

This kind of frame

Should i install a shelf in it to hold a bus board and switching psu?
uZeus is a no go because i have too much stuff to power for 1a.

BlinkyLights · Post by **BlinkyLights** » Sun Jun 23, 2019 11:15 pm

As soon as a delivery arrives this week I'll be getting rid of the flying bus cables that came with my uZeus and replacing those ribbon cable chains with Bus Boards from MDLR.

Anyone here done this specific thing before? Any tips or comments? Thanks.

cptnal · Post by **cptnal** » Mon Jun 24, 2019 5:33 am

sutekina bipu-on wrote:What would you guys suggest if i was to make a 12U open frame rack like this with the necessary extra rails to mount euro? I'm trying to figure out the best way to deal with distributing power.

This kind of frame

Should i install a shelf in it to hold a bus board and switching psu?
uZeus is a no go because i have too much stuff to power for 1a.

I briefly considered this option when I was researching a case for myself earlier this year. I decided against it mainly because I reckoned the cats would get at the power. Here's some of the discussions I had around the issues. Maybe you'll find something useful in there...

http://www.muffwiggler.com/forum/viewto ... 21078daf28

The_hitcher · Post by **The_hitcher** » Tue Jul 16, 2019 9:28 am

I have a healthy stack of these DC inverter power supply looking guys at my work they're chucking. Can these be applied to powering a rack?

JohnLRice · Post by **JohnLRice** » Tue Jul 16, 2019 10:27 am

The_hitcher wrote:I have a healthy stack of these DC inverter power supply looking guys at my work they're chucking. Can these be applied to powering a rack?

Well, at the very least grab 'em if they are free

since at the very least you could sell or trade them if you are patient?

Since there output is 48v DC, you'd need to further process their output with a DC to DC converter to get usable +-12v rails out if it. But you'll have to decide if the cost of the DC to DC converter and any other needed parts is worth the cost and effort or not.

The_hitcher · Post by **The_hitcher** » Tue Jul 16, 2019 10:34 am

Good call. Something like this? https://www.amazon.com/gp/offer-listing ... dition=all

JohnLRice · Post by **JohnLRice** » Tue Jul 16, 2019 11:06 am

The_hitcher wrote:Good call. Something like this? https://www.amazon.com/gp/offer-listing ... dition=all

Sort of but I wouldn't get the one you linked to since it only outputs one rail (you need a positive AND a negative 12v rail for eurorack along with a 0v rail.) Search someplace like Digikey or Mouser etc for DC to DC converters that will output the two voltages you need and can work with a a 48v input.

luchog · Post by **luchog** » Tue Jul 16, 2019 1:04 pm

sutekina bipu-on wrote:What would you guys suggest if i was to make a 12U open frame rack like this with the necessary extra rails to mount euro? I'm trying to figure out the best way to deal with distributing power.

This kind of frame

Should i install a shelf in it to hold a bus board and switching psu?
uZeus is a no go because i have too much stuff to power for 1a.

Metasonix RKP is double the hp of the uZeus, but it has 5A available on all three rails (it also requires three power bricks, which can become unwieldy). Probably overkill if you're not using Metasonix or other power-hungry tube-based modules.

The_hitcher · Post by **The_hitcher** » Tue Jul 16, 2019 1:14 pm

JohnLRice wrote:
The_hitcher wrote:Good call. Something like this? https://www.amazon.com/gp/offer-listing ... dition=all
Sort of but I wouldn't get the one you linked to since it only outputs one rail (you need a positive AND a negative 12v rail for eurorack along with a 0v rail.) Search someplace like Digikey or Mouser etc for DC to DC converters that will output the two voltages you need and can work with a a 48v input.

Thank you kindly! I have about 40 of them so if it's worth it for wigglers, I'd be happy to ship them out to ya'll if anyone is interested for the cost of shipping. I'd hate to see them at the scrap yard or landfill. Do you think it's worth it?

JohnLRice · Post by **JohnLRice** » Tue Jul 16, 2019 1:38 pm

The_hitcher wrote:
JohnLRice wrote:
The_hitcher wrote:Good call. Something like this? https://www.amazon.com/gp/offer-listing ... dition=all
Sort of but I wouldn't get the one you linked to since it only outputs one rail (you need a positive AND a negative 12v rail for eurorack along with a 0v rail.) Search someplace like Digikey or Mouser etc for DC to DC converters that will output the two voltages you need and can work with a a 48v input.
Thank you kindly! I have about 40 of them so if it's worth it for wigglers, I'd be happy to ship them out to ya'll if anyone is interested for the cost of shipping. I'd hate to see them at the scrap yard or landfill. Do you think it's worth it?

For reference:
https://www.meanwell-web.com/en-gb/ac-d ... --100f--48

That power supply has been obsoleted/discontinued, not sure why but Meanwell in particular does that quite often. I saw some one on eBay selling a used one for about $25 shipped. According to Allied Electronics the updated/replacement version, LRS-100-48, is about $20 plus shipping:
https://www.alliedelec.com/product/mean ... /70696540/

Also, converting 48v down to the two 12v rails might generate a lot of heat . . . maybe not much more then supplies designed from the ground up as eurorack supplies but I'd guess it would depend on the converter used.

It might be best to just put them on eBay, if you can sell them all over time (or are lucky enough that someone who needs a bunch of them sees it) for $10 or so plus shipping, that will be about $400 in your pocket to buy a nice eurorack supply and distribution!

The_hitcher · Post by **The_hitcher** » Tue Jul 16, 2019 2:10 pm

Ok, thanks for all your help. My boss won't be willing to keep them on the shelf so maybe I will do that.

Thanks again!

JohnLRice · Post by **JohnLRice** » Tue Jul 16, 2019 2:28 pm

The_hitcher wrote:Ok, thanks for all your help. My boss won't be willing to keep them on the shelf so maybe I will do that.

Thanks again!

Do a Google search on uses for 48 VDC power, I did out of curiosity and it seems that popularity is increasing in a lot of fields, even LED lighting, etc. Maybe with some research you'll find a good market where the supplies could be used as-is?

The_hitcher · Post by **The_hitcher** » Tue Jul 16, 2019 2:49 pm

Good point. We install RF networks for cell service inside buildings. Not sure why those in particular are on the shelf, but definitely a good idea. Thanks again!

Zentrix · Post by **Zentrix** » Mon Aug 19, 2019 7:07 pm

Apologies if this is a strange/nonsensical question...

I recall coming across discussions online when I was first setting up the power for my rack, where people were talking about using XLR connection jacks for power on their cases. (ie. a power brick/transformer that plugs into the wall on one end, on the other end terminates in a male/female type XLR connector which would be then plugged into it's mate on the eurorack case itself.)

Is this a completely insane idea? If not are there any tutorials about such a process that anyone can direct me to?

I have a feeling this may be a situation where I may be directed to an electrical engineering course at my local college... but I seem to have managed to wire up a Doepfer A-100 DIY kit without too much issue this far! I just really want to have a jack connector of some kind because at the moment my rack is married permanently to the power brick and it makes for a bit of clutter/confusion when moving the system around.

The_hitcher · Post by **The_hitcher** » Thu Sep 19, 2019 7:34 am

So I finally finished hooking up my dual Studio Bus boards to my Tip Top Access Panel. Some modules seem to work fine. Got the Mimeophon in the post and set right to hooking it up. Did not power on. All I had hooked up was an optomix and a Z8000 sequencer. What gives? I know it's not a lot to go on. I hooked the mimeophon into my mantis case and it works fine.

fowlutter · Post by **fowlutter** » Sat Sep 28, 2019 2:33 pm

Does anyone happen to know which pins on the Happy Nerding 3xVCA are -12v ?

It is not marked on the PCB. Thanks

monoreaction · Post by **monoreaction** » Fri Oct 25, 2019 12:43 pm

A lot of useful information on this thread. Thanks!

RLK · Post by **RLK** » Wed Nov 13, 2019 4:07 pm

Anyone familiar with this line of products?

https://eskatonicmodular.com/

Cannot find any info outside of the site and Reverb.com

DJMaytag · Post by **DJMaytag** » Thu Nov 21, 2019 2:51 pm

RLK wrote:Anyone familiar with this line of products?

https://eskatonicmodular.com/

Cannot find any info outside of the site and Reverb.com

I have some brackets coming in the mail today. Erik seems like a pretty good guy.

I believe he goes by Needham Woodworks on Instagram, and he makes some pretty spectacular cases. He is most definitely an excellent woodworker.

RLK · Post by **RLK** » Thu Nov 21, 2019 3:59 pm

DJMaytag wrote:
RLK wrote:Anyone familiar with this line of products?

https://eskatonicmodular.com/

Cannot find any info outside of the site and Reverb.com
I have some brackets coming in the mail today. Erik seems like a pretty good guy.

I believe he goes by Needham Woodworks on Instagram, and he makes some pretty spectacular cases. He is most definitely an excellent woodworker.

I appreciate the reply, BUT - I'm asking about the power supply products.

MUFF WIGGLER

MUFF WIGGLER

The Definitive Connecting Power Thread

Eskatonic Power supply products?

Re: Eskatonic Power supply products?

Re: Eskatonic Power supply products?