power supply unit.

Question

power supply unit.

hmhmhmhm (Computer)

(OP)

23 Feb 11 01:42

hi...
i am new to in creating something like power supply.
i need u guys to help me out here please.
we have this schematic to our power supply but
the problem now is that the fuse keeps on burning.
the spec. of the p.s. is 3 outputs:
1. for the 5 V, 2. for the +/-15V, 3. for the variable rating from 0 - 30 V..and the total current is 3 Amps, and also the current in each output is 3 A..

please take a look at the schematic..

thank u.

Skogsgurra (Electrical) · Answer 1 · 2011-02-23 01:53:37

If you pay attention to details and do some work on your own, you will soon find what causes the problem.

Do not expect us to work through that diagram. There are consulting engineers available for that kind of support.

Also, pay attention to other details like capital letters and punctuation. You are not texting on your cell phone - are you?

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

OperaHouse (Electrical) · Answer 2 · 2011-02-23 10:05:27

Look at the transistors. Either you don't know how to design or you don't know how to draw a schematic. The care to detail in this post seems you prefer to waste out time instead of your own.

MacGyverS2000 (Electrical) · Answer 3 · 2011-02-23 10:14:22

Ouch, that schematic is painful to the eyes... way too many unnecessary connections drawn wildly across the page, makes it difficult to pull out functional blocks.

Dan - Owner
http://www.Hi-TecDesigns.com

IRstuff (Aerospace) · Answer 4 · 2011-02-23 10:17:15

Is this for school?

TTFN

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OperaHouse (Electrical) · Answer 5 · 2011-02-23 12:17:27

I can only hope he is not getting paid. There are enough unemployed engineers who need his job. Don't know what you are doing besides toasting marshmellows with this circuit. Single transformer has to supply the highest voltage therefore 12A. That would be about 4A at the input. None of the transistors are connected so they do anything. If wired that way one of the regulators may have shorted regardless of manufacturers claimed thermak shutdown. Knowing what a 2n3904 and 2n3906 can take, I suspect without looking that a 2n3905 won't take 3A. You just don't deserve any help given how little effort you put into this.

I can't believe how lazy people are these days. Four 20ish people ran out of gas in front of my house. I was out walking the dog and offered them a gas can. The station was just around the corner. They asked me if I would get the gas. Then they all got on there cell phones trying to get someone to save them.

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power supply unit.