• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Will this work?

Status
Not open for further replies.

birdman0_o

Active Member
No I dont think so, you should look at this:
Rectifier circuits : DIODES AND RECTIFIERS
The middle of a center tap transformer is always ground. You can rectify each of the other two leads with just a diode as illustrated in my link and this will give you a full wave. Your second picture will not work because there is no ground. Perhaps you do not understand how a center tap transformer works and should look it up.

Mike
 

Ross Craney

New Member
Yes it will work though I'm not sure why you would want to.
 

rmn_tech

Member
No I dont think so, you should look at this:
Rectifier circuits : DIODES AND RECTIFIERS
The middle of a center tap transformer is always ground. You can rectify each of the other two leads with just a diode as illustrated in my link and this will give you a full wave. Your second picture will not work because there is no ground. Perhaps you do not understand how a center tap transformer works and should look it up.

Mike
Of course the second one will work why refer to ground at all ? it's just +ve / -ve

Both will in fact work.
 

amsm

New Member
Yes it will work though I'm not sure why you would want to.
I have a 24V transformer and two 12V transformers. I need some 24V current and as much 12V current as possible.
I need a common ground. If I connect the grounds, is it still going to work? I'm a bit paranoid, because a cap just blew up in my face the day before yesterday, though I don't think the circuit was exactly like this.
 

crutschow

Well-Known Member
Most Helpful Member
I have a 24V transformer and two 12V transformers. I need some 24V current and as much 12V current as possible.
I need a common ground. If I connect the grounds, is it still going to work? I'm a bit paranoid, because a cap just blew up in my face the day before yesterday, though I don't think the circuit was exactly like this.
If you have separate transformers, why are you showing a schematic with just one transformer?

Just connect the 24V transformer to a single bridge rectifier and the 12V transformers to a different single bridge rectifier.

To maximize the current you can connect the output of the two 12V transformers in parallel or run each output to it's own bridge rectifier.

If you run the transformers in parallel you have to make sure they have the same phase output; if they are opposite phase they will blow. (Check the phase by connecting one lead from each transformer together. Check the AC voltage between the other leads. It should read near 0V. If not reverse the leads to one of the transformers.)

You can connect all the bridge outputs to a common ground as long as none of the transformer outputs are grounded.
 

amsm

New Member
OK, I think everything is in order, but I submit it for peer review. There will be caps in appropriate places, of course, to smooth out any ripple.
 

Attachments

Diver300

Well-Known Member
Most Helpful Member
Sorry, but that won't work.

The two bridge rectifiers on the 24 V transformer combine to give you 24 V on the 12V line.

I have shown one of the current paths on my drawing. There are other problems as well. It is generally not a good idea to have more than one rectifier on one transformer.
 

Attachments

amsm

New Member
The two bridge rectifiers on the 24 V transformer combine to give you 24 V on the 12V line.
Jeez! I'm really rusty, to have missed that!
Well, that explains why the capacitor exploded! Thank for your input!

Would omitting "B1" correct the problem and still give me some amperage?
 
Last edited:

crutschow

Well-Known Member
Most Helpful Member
You only want one bridge rectifier per transformer winding, you can't use two to give different voltages from the center tap.
 

crutschow

Well-Known Member
Most Helpful Member

mneary

New Member
The voltages will be different, sometimes double, sometimes half, of what you expect. Sometimes the voltages will be near zero until the magic smoke escapes from one or more diodes or transformers.

Keep the circuit simple enough to understand. There is no reason to make complex diode circuits. The experts don't do it, and there is even less reason for the novice to do so.
 
Last edited:

Sceadwian

Banned
Why are you trying something like this in the first place? Use a single bridge rectifier and stop using the center tap of the transformer.
 
Status
Not open for further replies.

Latest threads

EE World Online Articles

Loading
Top