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My new DIY bench power supply: 0..48V 0..20A (max power 500W)

rin67630

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Nort-Rhine-Westphlia Germany
Build from - 4x surplus computer mains adapters 24v / 5A and a DPS 5020 + USB communication module
The 4 mains adapters are connected in a 2P-2S configuration to provide 48V-10A power to the programmable power supply.
This one, being a buck converter, can provide more than 10A at lower voltages e.g. up to 18A at 13,6V.
The DPS 5020 are pretty good and reliable modules that are able to be set up to even very low CC values and maintains these accurately.
Beside that, the power supply can be programmed over an (optically isolated) USB-port.
You may also purchase the Bluetooth variant for a completely wireless communication.



Total BOM cost ~60$
I could purchase the computer mains adapters 24v / 5A for ~$4 each. You probably will find in your vicinity an electronic surplus store, that sells this kind of power supplies for old computers as well. They are very common and of an excellent quality.
The DPS 5020 in the USB communication version is sold at your favorite Chinese outlet for around $40.

The provided PC application is not that exciting, but GitHub is full with corresponding software. In the following weeks I will surely program a battery loader with different charging profiles using a cloud service as a remote display with trend charts to monitor the loading process.
 
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That's luscious.

When can we expect the complete BOM and build instructions? :)
 
The build is really straightforward, not rocket science.
You connect all AC inputs in parallel*, connect the DC outputs in 2S-2P configuration to the DC input of the DSP5020, and the output of it to the banana sockets. That's it!
IMHO one could also scale the solution with even more mains adapters e.g a 2S-4P configuration, if you would need more amps at higher voltages, I just did not need more.

* personally I did not use the mains plugs and did directly solder the AC wires to the sockets, drowning everything in hot glue, which makes them much more compact build, but that is surely not according to your electrical regulations.
 
Build from - 4x surplus computer mains adapters 24v / 5A and a DPS 5020 + USB communication module
The 4 mains adapters are connected in a 2P-2S configuration to provide 48V-10A power to the programmable power supply.
This one, being a buck converter, can provide more than 10A at lower voltages e.g. up to 18A at 13,6V.
The DPS 5020 are pretty good and reliable modules that are able to be set up to even very low CC values and maintains these accurately.
Beside that, the power supply can be programmed over an (optically isolated) USB-port.
You may also purchase the Bluetooth variant for a completely wireless communication.



Total BOM cost ~60$
I could purchase the computer mains adapters 24v / 5A for ~$4 each. You probably will find in your vicinity an electronic surplus store, that sells this kind of power supplies for old computers as well. They are very common and of an excellent quality.
The DPS 5020 in the USB communication version is sold at your favorite Chinese outlet for around $40.

The provided PC application is not that exciting, but GitHub is full with corresponding software. In the following weeks I will surely program a battery loader with different charging profiles using a cloud service as a remote display with trend charts to monitor the loading process.
Sounds good, Jehu built similar from server psus, it would be nice to have variable cc and cv adjustments, a display, etc.
Pics? Wiring? Plans?
 
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Here is the pic.
No need for a schematic, it's no rocket science: you wire the outputs of the 4 computer PSU's in a 2S-2P config to the input of the DPS5020 device.
Only caveat: my used PSUs had the mains earth wired to the minus of the output: just take care to only wire the earth on ONE PSU only, so do not use the original cords...
That's it.
The DPS5020 provides all you need: CV-CC 3 fold color display, Serial / Bluetooth control.
 
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If you need not more than 12A and are ready to solder on a prototyping board:
Drok-Juntek-on Steroids is a WiFi-Cloud enabled programmable power supply based e.g on d DROK DPS6012 , that can -also be used as a MPPT-charger and provides charger profiles and Ah statistics. It is really packed with features...
Drok-Juntek on Steroids.
 

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The DPS 5020 is a great little module setup --Be very careful not to Reverse Polarity when charging batteries --No Protection there --It fries the board in an instant --- Yes I'm the Dummy that did it twice --There's plenty of info on BLF about the 5020

 
The DPS 5020 is a great little module setup --Be very careful not to Reverse Polarity when charging batteries --No Protection there --It fries the board in an instant ...
Not only Reverse Polarity, but also Reverse Current: the battery voltage is present at the input terminals.
Briefly short them when the battery is connected and enjoy the magic blue smoke...
The computer PSUs I used had no problem with that reverse feed, but you should test....
 
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