Power supply setup


#1

Hi folks,

This question is not NR related, but I think enough brains are avaliable here... I have lots of devices, all with their own voltage levels (5v / 7,5v / 9v / ...). Currently I have some din-rail adapters to 12v, and then I use automotive dc-dc converters from aliexpress to go to some specific voltage levels.

However I would like to build a better solution that:

  • Is nice to look at, e.g. everything din-rail?
  • Is all CE approved
  • Has all kind of fuses. Don't want any of my devices to corrupt my setup
  • Has adjustable voltage levels. So I can use the same converters for alk devices.
  • Has some visual interface (e.g. LEDs) to see immediately where something is wrong
  • Is affordable, since Im married (with a female prototype version 0.0). So I need to save some money to be able to buy a massive amount f shoes :slight_smile:

Thanks!!
Bart


#2

Have a look at the Mean Well MDR Range.
https://www.meanwell.co.uk/mdr-20-12.html

Download the PDF, there are several models there.


#3

Hi Garry,

Thanks!

Had seen those also, but not sure if I can use them?

I have devices with 7,5v power adapter for example. Don't think I can adjust one of these power supplies to 7,5v?


#4

Bart,
a voltage regulator on the output of the 12V model should do it.


#5

https://www.st.com/content/st_com/en/products/power-management/linear-voltage-regulators/standard-voltage-regulators/l78s.html


#6

Garry,

Currently I have the following setup, a bit similar to what you describe:
image

The grey Siemens (which were way too expensive!) converters do the 230VAC to 12VDC conversion. To each of those converters I have added multiple DC-DC converters (for each of my devices), which you can see at the back of the closet:

image

These (automotive) DC-DC converters are rather cheap on Ali. They have a fixed output voltage, but I managed to find a separate type for each output voltage that I needed. But they have a few disadvantages:

  • As you can see it becomes quite a mess, since they are not din rail.
  • One of these was corrupt this morning, and I took me an hour to figure out what was wrong (since they don't have a LED or any other indication). I could a led myself, but then it is again becoming more messy...

Afterwards I also bought this one from Ali, since the output voltage is adjustable and nicely displayed on the 7-segment display:

image

But here again not easy to fit them nicely into a closet, and you still need separate AC/DC converters to power them.

Your solution would be much more decent: a separate adjustable din-rail for each device. If I could just adjust the voltage to a 'random' value...

All tips are welcome, since I'm not an electronics expert.


#7

I use a Meanwell 24V DC power supply (Amazon) and a RUIDENG DPS3005 32V 5A. The DPS gives me the ability to adjust the power output, I have a setup with 1 24V supply and 3 DPS devices. I have some older boards that need triple supplies.

There are rules with this, all the DPS devices can't try to use more than 80% of the 24V power supplies rated current.. I generally don't need more than 50%.

The whole thing is pretty easy to wire up. I don't have a case for it but I'm also not using it as a permanent supply. Just as a test bench power supply.


#8

@ncherry solution looks good, if a little expensive. Less shoes then? :slight_smile:


#9

Hi Neil (@ncherry),
The ouput voltage range (0V-32.00V) is indeed something that could be very useful!
You say you have 3 DPS devices. Do you mean you have 3 of such screens or a single screen that communicates with 3 USB or bluetooth pcb's ?

@ghayne. I should really keep the price a bit under control, because less shoes is not a valid option in wife version 0.0. Seems to be a known bug :joy:


#10

https://www.aliexpress.com/item/-/32837531202.html?spm=a2g0s.13010208.99999999.259.4cb03c00cxkHAD


#11

Here is another DC-DC converter from ebay for only 6,29 USD which looks pretty cool:

image

The input voltage range is 5-23V, and the output voltage range is adjustable between 0-16.5V. I could power a series of those converters with a SINGLE power supply (like Neil did) which can produce enough amperes. But the main problem is that I have no din-rail case. Or another case that could be nicely fitted into some kind of closet. Anybody ever seen a nice looking (and expandable) setup?

EDIT: On the above ebay link the same module can be bought, together with an acrylic case for 7,34 USD:
image

Perhaps I can din-rail mount this case somehow, by using those brackets from Aliexpress for only 1,4 USD for a pair of brackets:
image

Total amount would be 8,74 USD for each converter, which should survive the wife-acceptance-validation-algorithm...


#12

Not a bug, an expensive feature.

I have 3 separate DPS devices on the one power supply. I haven't started using the communications interface yet.


#13

Had found last night also some other Meanwell devices. Not very expensive, but no voltages between 5,5 V en 10 V. Strange. Have send them a mail about it, but don't expect a positive answer ...

@ncherry: I like the display part of your solution, since I allows me to do some troubleshooting very quickly. So meanwhile I have been looking for some other modules on Aliexpress (with display and acrylic case). Don't know which to choose... Does anybody can assist me in choosing the best option (e.g. on some devices I don't find info about short-circuit and terminal protections ...)?

  • This is the same as the one on ebay for 10,5 USD:

    image

    input : 5 ~ 23 V DC (3A max)
    output : 0 ~ 16.5 V DC
    precision : 1%

  • This is bit less expensive, but you need to pay shipping. In my case (Belgium) total cost is 9 USD:

    image

    input : 5 ~ 36 VDC (5A max)
    output : 1.25 ~ 32 VDC
    short-circuit protection + heating protection

  • This is already available at 4,58 USD:
    image

    Input : 5 ~ 23 VDC (3A max)
    Output : 0 ~ 16.5 VDC verstelbare (Het bespaart de laatste set spanning automatisch)

  • This one has an intermediate price of 7,81 USD:

    image

    Input : 6.5 ~ 36 VDC
    Output : 1.2 ~ 32 VDC (3,5 A max)
    Short-circuit protection and switched input protection
    They claim the device can work stable for longer time on 3,5A

P.S. I'm not one of the main shareholder of Aliexpress :sunglasses: