0-30 Vdc Stabilized Power Supply

[hana_moh]

THANKS TO YOU

 

[egres]

hi everybody.. here are some photos of mine power supply.. no housing yet, but few "tests"

list of changes: (partlist by audioguru, the tuned one, but few parts changed)
power transistors:
-a pair of BD249C (100V, 25A, 40A_peak, 125W at 25

View attachment 40130

View attachment 40131

 

[egres]

two more:

View attachment 40132

View attachment 40133

 

[egres]

and a video, thats all, thanks for your attention

egres

pc050163.rar

 

[audioguru2]

Hi Egres,
My browser displays a square box instead of the "E's" in your name. So I called you Grs before.

Your project is very powerful. I think its good voltage regulation will improve with thicker wires.

I didn't see the car headlight blowup in your video. 

 

[egres]

AG,

thats ok, i thought something with fonts will be wrong

well.. i am sure you know that those bulbs must be cooled.. atkeast with air.. when i wired it in series, and connected 24 volts for few seconds, it did not blew up, but my table is a little brown in that place .. and the bulb started smoking .. but i did not wanted to sacrifice it for my experiments

 

[ddav]

hi everybody

I used LM343( russian analog is K1408ud1, max power supply +-40v) instead of TL081. It works normally. And also R7 has reduced up to 0,22R and R18 has increased up to 82k.

 

[audioguru2]

Hi Ddav,
Welcome to our forum. ;D
It is good that you found some high voltage opamps for good reliability.

 

[hana_moh]

thanks to the Boss "audioguru"
all is ok.

View attachment 40192

View attachment 40193

 

[audioguru2]

Hi Hanna,
Your project looks nice.
I hope nothing blows up because the voltage of your 36V transformer is much too high.

 

[hana_moh]

thanks to you only LCD problem i will change as soon as possible
about "36 transformer is much too high" under test
thanks for interest and max follow up

 

[phaethom]

hello
i made thid power suply, but i just have a voltage between 0.43 and 19.98 volts
what can do?

 

[audioguru2]

what can do?

Hi Phaethom,
Welcome to our forum. ;D

Did you make the original project or the modified one?
Did you substitute any parts?

1) What is the DC volatge across C1?
2) what is the negative DC voltage at pin 4 of U2?
3) What is the positive DC voltage at pin 6 of U1?

 

[phaethom]

i made by original project, and dont chage anything,
c1-33 volts
4-u2-(-4,6 volts)
6 u1 (10 volts)

sory but  my english is bad

 

[audioguru2]

Hi Phaethom,
1) The voltage of C1 is low because a 24VAC transformer is 25VAC without a load and its peak is 35.4V. the rectifiers drop it to about only 34VDC.
2) Pin 4 of U2 has a 5.6V zener diode. Maybe you used one that is made for a high current, so its voltage is low in this circuit.
3) Pin 6 of U1 should be 11.2V but maybe you used a zener diode made for a high current so its voltage is low in this circuit.

Even with your low voltages, the output amplifier has a gain of 3.07 so your max output voltage should be near +30.7V, not just +19.98V. R11 and R12 determine the gain of the output amplifier. Check their values.

What is the part number of the 5.6V zener diodes that you used?

Without a load and with the voltage pot and the current pot turned to max, is the current-regulating LED turned on? What is the output voltage? What is the voltage at pin 6 of U2?

 

[phaethom]

now i have voltage between 21.7 and 31
zener part number is 2p d5

 

[phaethom]

suddenly my voltage on output is between 21.7 and 31

 

[audioguru2]

Hi Phaethom,
I don't know your zener diodes.
I think your project has something loose inside.

 

[phaethom]

ok.
im gonna change it

 

[arman_linkin]

(exuse me for my bad english.i am only a  learner)
hi to all
I want to built this power supply.but I have a question :
1.if I use an ammeter for it ...it will show the ampere that the load use or the ampere that was set ?

thank a lottttttttttt.
Arman 

View attachment 40202