#184

I wouldn’t recommend maxing out you PSU. You need mA headroom if you don’t want to fry some of your modules, specially for digital modules that consume more when booting up.

1 Like
#185

Eurorack people should move away from flying buses as a form of distribution: you start adding noise to your system.
You need something with thicker copper lines, like a bussboards. Personally, I use LIBB from Genus Modu

3 Likes
#186

I think I’m just going to get another PS for the Octatrack.

Still, as an academic exercise… I have a Ripcord battery adapter that runs the OT just fine which has a 750 mA limit at 12V. I would be really, really surprised if the OT actually ever pulled 2A. That seems like a boatload of current. Possibly inrush at startup, but the battery pack solution seems to work fine.

The Elektron site says 7 W typical draw, which at 12 V is less than 600 mA.

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#187

Sorry for my misleading answer. I didn’t want to imply that the OT uses 2A of current. Yes, that would be a boatload. I just assumed they would go with a PS with double amount of needed current as safety margin. If they state 7W then less than 600mA it is.

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#188

I’m not sure how well it would fit your use case, but Trogtronic’s power supplies have served me very well. I would definitely recommend their stuff!

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#189

There is no way that will fit in the POD he was talking about :slight_smile: But yeah, a low impedance busboard is better when you can afford the space. Or just screw everything into busbars as Graham Hinton would have you do.

2 Likes
#190

I got the Hinton bars in one of my rigs. Terrifying and does what it says on the box.

2 Likes
#191

I just picked up 4m of these pre tapped copper bus bars, as inspired by the Hinton system

It will be slightly higher resistance than a chunky 10mm square bit of aluminium but the price was right!

What do you have powering that case? I’m looking at linear PSUs at the moment, considering this Bel Power HCC15-3-AG or Emerson SLD-12-3434-12T. Looking at around 3A +12V

1 Like
#192

I just have a 4ms row power with a big brick attached to it. Hinton of course really hates it but it’s a mobile case for fitting in the overhead of an airplane. He’d rather I was running a Meanwell.

#193

good Morning,

I apologize if my post has been covered by other posts. I am afflicted with ignorance when it comes to Electricity despite my long-standing use of electronic instruments.

Recently, I acquired a very awesome eurorack case with a Doepfer A-100PSU2 inside. Nice. But it will only run a couple modules at a time. Lame. I used a multi-meter tool to measure the VOLTS and saw 12v and -12v on the meter so the power is there.

When I plug in too many modules, they simply fail to power on. I am not running any 5v modules as I do not believe this power supply supports 5v modules.

Any ideas of how to fix this PSU or have I encountered a lost cause?

#194

It could be a power header on the supply, a cable or a module…I’d say first do things 1 by 1 eliminating variables to see if it’s one of those things. As a side note, make sure to turn the system off plug things in and turn back on. Euro power is not hotpluggable

#195

How many modules are you running? What is the current draw of the modules? Without that information, it’s hard to give any clear advice.

#196

If you have your modules in modulargrid you should be able to see how many amps those modules need. Your power supply looks like it can supply 1200mA on the 12V and -12V rails but if there is an external brick supplying power to it you should make sure that it can also supply the appropriate amount of amps. So the total amps that your modules draw should be less than I think it was like 80% of the amps of your power supply if I remember correctly.

#197

In regards to busbars I use one for all my grounds. I’ve got busboards in there to make hooking modules up easy but I still tie off all my grounds to a single bar. I suppose my thought was I could have stars in my stars in regards to grounding and I haven’t ran into any issues using two metatronic mods PSUs. Btw, metatronic mods has a wild busbar distroboard solution but I’m using their older style busboards.

#198

Thank you for your thoughts on my power supply dilemma, fellows.

I only have five modules plugged in; the current draw is very small: 324 mA +12V | 188 mA -12V

No power brick, just a large cord.

I have never plugged a eurorack module in with the case power on due to Fear.

All the modules which have failed to power on in this case work just fine in a Mantis case.

#199

That certainly seems like something is awry.
The PSU2 is the one with the toroidal transformer IIRC.
Are you using the case in a different country to its origin?
Take some photos of the info on the transformer and some board photos. Also check the fuses.

#200

I’m in the U.S. and the case came from New Jersey. Not sure where it was before that, if anywhere.

Here are photos of the top & bottom boards as well as the PSU. Not sure if they’re useful in any way.

The seller did include some extra fuses. Do you happen to know where I ought to look for them in the case?

Thanks much.

20201002_071843
20201002_0718434032×2268 2.21 MB
20201002_071910
20201002_0719104032×2268 2.92 MB
20201002_071904
20201002_0719044032×2268 2 MB

#201

Thanks for the photos.
The transformer is unmarked so that’s generally a sign of it being the 115v version, which is correct. The rectifier must be working, and the caps seem fine. Perhaps there’s an issue with the regulators that are under the heatsinks, but that’s conjecture.
The busboards shouldn’t be an issue either, although one of the pins is bent on the -12v side (visible in your second photo) so be careful of that.
The fuse is in the power socket - you can pull out a tray between the on switch and the three-pin socket. It should be an 800ma slow-blow fuse (it will have a “T” marked on it)
You can see this info on page 4 of this pdf:
http://www.doepfer.de/a100_man/A100_short_form_manual.pdf
If you don’t mind, please take a photo of the wiring both to the busboards and to the power switch. Please unplug it from the mains so there’s no live voltage to zap you!
Actually, I’d also visually inspect the pins on the busboards - as one pin is visibly bent, there may be others that are in a riskier position, such as touching each other etc.
Also, when the case is powered up without modules, do the LEDs light on both the PSU board and the busboards?

#202

hello, You’re the best, thanks so much for taking the time to think about this with me.

I replaced the fuse (dubious solution) and straightened all bent pins.

I removed all the modules from the case and observed the lights turn on both on the power supply and boards.

I replaced the modules one by one until, in a blaze of solar light, adding a module caused all the modules to not power on.

I moved that module to a different header and everything works OK now.

So, probably a few bad headers in there, which is OK because there are way more than I could feasibly use.

Thanks again.

1 Like
#203

You’re welcome!
From a robustness point of view, I’d definitely take out that busboard so you can inspect the reverse for any cold solder joints etc, especially where you were seeing problems.
You could also try continuity testing the boards to see if there are any broken traces between headers.

1 Like