# how to make 0-24v 5amp regulated power supply

#### VickySalunkhe

Joined Sep 17, 2017
3
I am noobie so plz help and co-operate

I was thinking to use 12-0-12V 5A center tap transformer

I know by connecting 2 12v wires I'll be getting required 24v ac but i am stucked at which components shall be used and how for making regulated power supply

My ultimate aim is to make an 48v 5amp power supply to run an electric motor

So just thought I'll make 2 24v 5amp power supplies which could then be connected in series for getting the required 48v 5Amp as an output

If you could help me with designing a circuit for making an 24v 5amp regulated power supply that will be really helpful

I have found a circuit for 24V 1amp
But my requirement is for 5amp and i am not not sure which components should be replaced

Any suggestion and help will be appreciated

Thnks

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#### Alec_t

Joined Sep 17, 2013
11,389
I think you'll find it a lot cheaper, and certainly easier, to buy a ready-made switched-mode power supply. Have you priced a 12-0-12V 5A conventional transformer? .

#### Janis59

Joined Aug 21, 2017
1,187
Mjaa, today the analog transformer became so expensive that more easy it is to wind by own.But if You havent right core and indeed that core You have support the power what is needed (and You are very unwilling to rewind the secondary, then make up the "Boost-Up type DC/DC converter" like https://en.wikipedia.org/wiki/Boost_converterhttps://en.wikipedia.org/wiki/Boost_converter
However You have an another option - just apply a voltage doubler like https://en.wikipedia.org/wiki/Voltage_doubler, but the capacitor value I suspect will be unrealistically large in this case. If the aim would be the 48V+/- 3V then tau(RC)~ 48/3*10 msec or 0,16 sec what for 48V/5A=9,6 Ohm gives a capacitor around 16 000 uF. Sure the DC/DC will take a smaller place.
But dont throw away the idea about rewinding the core Yourself.

#### k7elp60

Joined Nov 4, 2008
562
I am noobie so plz help and co-operate

I was thinking to use 12-0-12V 5A center tap transformer

I know by connecting 2 12v wires I'll be getting required 24v ac but i am stucked at which components shall be used and how for making regulated power supply

My ultimate aim is to make an 48v 5amp power supply to run an electric motor

So just thought I'll make 2 24v 5amp power supplies which could then be connected in series for getting the required 48v 5Amp as an output

If you could help me with designing a circuit for making an 24v 5amp regulated power supply that will be really helpful

I have found a circuit for 24V 1amp
But my requirement is for 5amp and i am not not sure which components should be replaced

Any suggestion and help will be appreciated

Thnks
If you make some changes to the circuit you posted it will work. Replace the LM317 with a LM338. Increase your filter capacitance to 15,000uF or greater. Replace the diode rectifiers to 6A diodes(2.5A diodes would work) Make sure you have large enough heatsink for the LM338.

#### VickySalunkhe

Joined Sep 17, 2017
3
If you make some changes to the circuit you posted it will work. Replace the LM317 with a LM338. Increase your filter capacitance to 15,000uF or greater. Replace the diode rectifiers to 6A diodes(2.5A diodes would work) Make sure you have large enough heatsink for the LM338.
thanks k7elp60

can you plz help me by telling how did you came to the conclusion of using those components
and do i need to change the resistors as well ?
thanks a lot

#### Dodgydave

Joined Jun 22, 2012
9,200
Ditch the Lm317 and use a Lm2596 or other buck converter, less waste, less heat.

#### k7elp60

Joined Nov 4, 2008
562
thanks k7elp60

can you plz help me by telling how did you came to the conclusion of using those components
and do i need to change the resistors as well ?
thanks a lot
The first thing is the LM317 will not handle 5A but the LM338 will. The rule of thumb for filter capacitors that I use all the time is 3000uF for each amp of DC supplied current. The resistors do not need to be changed. The 1N4007 diodes are 1A,(some data sheets may say 2.5A) but I think they are 1A because of their physical size.

Joined Feb 20, 2016
3,564
There are a range of these sort of devices on EBay or Aliexpress....

If you want a variable supply over that voltage range, go switch mode. Otherwise you will be wasting a lot of power as heat when on low volts out.
For a motor, you will probably get away with an unregulated supply quite well.
And even a rectified AC without much filtering if any. It does depend a bit on the motor you have.

#### Janis59

Joined Aug 21, 2017
1,187
I was many times bought the Chinese 480W AC/DC (24V 20A for 25 USD) so I know well there are plenty on ebay such 240W what corresponds Your 48V 5A, and them cost about 15 USD. Seek it with phrase - AC-DC switched mode power supply