That supply is described as “a single-output high-precision DC supply” so GND there is mains ground, not 0 V.
(ground and earth can mean a lot of things. I recommend using “0 V” for circuit ground, since that’s what it is.)
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Okayyy thank you a lot! I will cancel my order then
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I found this topic so I’ll move my question here where it’s more appropriate. I’m curious whether Microbus with Expandobus expansion (+7 power headers) is actually capable of powering 15 modules. Do you have any experience with it? Are you using it in your system?
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Depends on the modules and on the wall wart you feed it with. A 1A wall wart will probably give you a good 500 mA on the +12V rail. A rough guess of ~50 mA per module gets you to about 10 modules, but the actual number can vary all over the place — most commercial modules have current requirements listed, if they don’t you can measure. A 2A wall wart would likely get you to 15 modules… likely.
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Thank you, I’ll probably go for it now and later will add another power supply.
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anyone ever try one of these with a pc power supply? lol
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I have the dangerous prototypes one and it works fine (with the usual caveats about switched supplies, etc). No idea how robust the clones are…
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Come to that, I seem to have half a dozen redundant ThinkPad power supplies due to various forms of accelerated entropy being brought to bear on my laptops. I must take a closer look at whether laptop power supplies can be used for synths.
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I power my 150hp 12 U Eurorack case from two ancient 12V laptop supplies and they don’t even get warm.
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I picked up some of these ATX adapters a while ago only to discover I’d binned my stash of atx supplies. Sing out should anyone need one.
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I just got a microbus for my 84hp. Haven’t filled up one of the 3u rows yet. I started noticing a weird thing as I swapped different modules in and out. With more than 6 modules in, totaling around 300ma draw, several of my modules began behaving unpredictably. Akemie’s Taiko loses the ability to have stable pitch tracking and will begin to pitch shift on it’s own. Plaits will change the range of all modulation inputs making the Model CV behave randomly as well.
I’m using a 1A 12vac electro harmonix adapter.
To check things out a bit I checked the current draw between the adapter and the microbus as I plugged and unplugged different modules.
Things started getting weird when the current went up above 280ma or so. Any idea why this might be?
I also noticed that when plugging in the Intellijel Noise Tools that the current reading went down considerably instead of up. That’s also a mystery to me.
Should I check the current between the microbus and each module?
Check if the voltage at the input of the microbus while plugin modules.
1A on the adapter is just advertising…
The voltage reads 13.4vac and holds steady at the microbus input with all different module configurations.
I guess one other consideration is grounding. I’m using a wood case with wood rails. All ground connections on the moduleshave continuity through the microbus and with each other. I couldn’t see why the panels should need an additional ground path but I have read that people think this is necessary.
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I don’t know how it’s done in Eurorack but a lot of tears can be saved by a good thick bus bar and dedicated ground wires. It may be one more connection to unscrew when you move a module, but if you’re going to be moving modules around a lot you’ll be glad to have one vital connection you don’t need to worry about.
I have a complete DIY solution here that works wonderfully in combination. The bus board is my own design, the PSU is from the internet, but pretty much the same as that of MFOS. I only enlarged the circuit board a bit so that it can also be attached.
I can verify both with a clear conscience!
I can recommend this AC wall wart, it is available in different versions and it is cheap. I use them too. I have the 1A model and so far no problems with almost 20 modules.
And here the busboard, which you can of course extend or shorten as you wish. Very easy. It is important to pay attention to the trace cuts under the resistors!
Here are a few more photos of mine:
Here is my Desk PSU with a smaller version of my bus board:
Here is the longer version. In the upper layout it is a little wider so that it can also be attached properly. These were the first versions, but still work fine 
And finally again in my case
I hope this helps a little. Greetings THOGRE
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Are there problems with connecting ground through the six wires on the ribbon cable and through the headers? I can’t think of what problems would come up with this setup.
If you create a separate ground path is it a good idea to cut out the path through the ribbon cable to eliminate potential ground loops?
Also, where did you find the strip board in big enough pieces to make those bus boards?
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Yes, I think you have some serious problem, how much power is your wall wart? I got these stripboards from here. But I would not buy these again, the quality is not good. That’s why I also built in the pin headers to easily extend the slightly shorter stripboards.
No, there are no problems at all with the GND and it is even the standard in the Eurorack area, I have included a picture here for you.
I hope I understood your questions correctly
Cheers THOGRE
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Ahh, I missed that you have a 1A wall wart. What kind of modules do you have? There are some who need a little more power than others, but I don’t think that there should be problems with 1A and 6 modules.