Modular Power Supplies


#82

After my DIY MFOS wallwart PSU died I bought one of these on Amazon, cheap and is working fine for me so far http://www.sf-innovations.co.uk/eurorack-psu.html


#83

Any help appreciated for this novice query… ! … Would it hurt to swap a Meanwell GSM60A15-P1J for a GST40A12-P1J to see if it solves a power problem? I have the 4U 104hp Intellijel case (GSM60A15-P1J) and the Erica Synths 6U 104hp travel case (GST40A12-P1J) and a grounding problem with Pressure Points in the Erica case when its not plugged into the mixer. I’m concerned that at an upcoming show the wall power may not be grounded properly for the mixer so I wanted to check if the GSM60A15-P1J (which I read on MW may fix the grounding issue) would be a solution. I know that the voltage and wattage are different but not sure how this matters and if there is potential to destroy modules. In fact its totally possible that I could accidentally swap them so its a good idea to know this anyway.

EDIT: Maybe someone has a suggestion for a direct swap of the GST40A12-P1J that is properly grounded for the Erica case (I read about these grounding issues on MW and also the mod on the which I will perform if needed)


#84

most meanwell power supplies in the series you’re referencing come in the gsm and gst versions. the number later in the model number indicates voltage (12 vs 15 vs whatever). if you look at the pin assignment portion of the datasheet, it will typically indicate if -v is connected to ac frame ground (which is recommended for some capacitive touch modules to work properly).

it is important that you look at this for the exact adapter you are considering, since the t and m designations are inconsistent with respect to grounding scheme across the line. typically in the lower amperage/barrel connector adapters, -v is connected to frame ground in the gsm version.

so, in your case, a direct replacement for GST40A12-P1J would be GSM40A12-P1J, which does have -v connected to ac fg.

to answer the question "Would it hurt to swap a Meanwell GSM60A15-P1J for a GST40A12-P1J to see if it solves a power problem? ", that depends if the erica synths travel case power supply can accept an incoming voltage of 15 volts instead of 12.


#85

Thanks for a complete and succinct answer. I think I will try the GSM power supply when I can get one and not try the mod on the other. As for the show, I think I will take the chance… and a long extension cord


#86

Hi all,

I am having some power related issues with my system.

Sometimes after 5 minutes, other times after 30 minutes, its arbitrary, my master clock (Wogglebug) suddenly slows down to less than half its rate, and I begin to hear what sounds like ripple noise from my delay module.

The noise stays and the clock remains slow until I power cycle.

I am at 1346ma (+12v) / 567ma (-12v) according to Modulargrid data sheet, my power supply is an Intellijel TPS30 (rated at 1.5A on both the ±12v) with a Meanwell GSM60A15 (60 watt / 15v) switching power supply.

Does anyone here know what the issue is? Am I going over the 1.5A? Is the Meanwell dropping voltage? Or is the TPS30 maxing out at 1346ma? Or something else altogether?

Thanks in advance for your advices.


#87

I think it’s just not advisable to be that close to your peak. The power ratings for modules are an average, so conceivably the various “power high tides” could be conspiring against you to push you up to that 1.5A.


#88

I see… So even say changing the power brick to an 18v version wouldn’t help? I didn’t think that 1346ma was already close to the edge! :smiley:


#89

I don’t know my Ohm’s law that well, but I think that if you were to change the power brick, you’d want to up the wattage, not the voltage.

But! I’m not sure that’s a smart idea: the bus board inside your case itself might not be designed to be pushed harder than the power brick it came with.


#90

What would you say would be a safe max A consumption is going with Modulargrid number?


#91

again, I don’t wanna seem more of an expert than I am (I’m really not one), but I read once on The Other Site to aim to keep it at more like two thirds, so if pressed, I’d say 1Amp?


#92

To confirm that it’s power related, I would try taking your most power hungry module out of the case to see if that changes anything. When I was using a submodular case, I remember reading warnings not to push the intellijel power beyond a certain point due to some tolerance of the power connector the case used, so maybe that’s worth looking into too? Are you using the 4 hp power entry module or something else?


#93

I suspect it is, because I took out already 1 module as with that module connected, I would immediately get the slowed clock and ripple noise the moment I press play on the sequencer. After disconnecting it (it consumed 43ma on the +12v), I now only get the problem after 30 or so minutes of use.


#94

Hmm – it’s still not confirmed that it’s power if you’re still getting the issue right? You may need to try different configurations of modules too to see if one module is causing it.


#95

make sure to calculate consumption on +5v bus too.
also if you’re using any of monome trilogy modules (white whale, earthsea, meadowphysics) with grid attached this can add significantly (up to 500mA) to +5.


#96

Actually I’ve nothing on the 5v as I’m using Ansible, and also externally powering it.


#97

I think it might still be power related as I only reduced the whole power consumption by 43ma after removing that module. Guess 43ma bought me 30 minutes of usage :slight_smile:

I’ll take out another module and see if the issue goes away.


#98

Going by the amps you’d need 3A just for the 12V rails and the power brick is rated at 4A max. I’m not sure how they arrive at those max current ratings for TPS30 but to me they add up to more than 30W. Don’t trust MG, it’s worth double-checking the specs for each module you have and keep in mind they do occasionally exceed their ratings. I’d change the power supply (last time that solved my then similar problem)


#99

Your mean to change the whole TPS 30? Or just the power brick?


#100

the board and the brick. 1.4A that you’re drawing on the +12V rail is too close to its max rating anyway


#101

Will have to reduce modules for now then as I’m too broke to buy a new power supply at the moment :frowning: