What will happen if i connect a 120vAC to 12vDC transformer to 6vAC?

Normally, 120Vac, transformer, 9.3Vac, diodes -1.2V, capacitor, 12Vdc.
Experiment, 6Vac, transformer, 0.45Vac, diodes -1.2V, capacitor, 0Vdc.
I think the transformer will make such a small voltage that it cannot turn on one diode, or two diodes of a full wave bridge.

ronsimpson said:

Normally, 120Vac, transformer, 9.3Vac, diodes -1.2V, capacitor, 12Vdc.
Experiment, 6Vac, transformer, 0.45Vac, diodes -1.2V, capacitor, 0Vdc.
I think the transformer will make such a small voltage that it cannot turn on one diode, or two diodes of a full wave bridge.

Click to expand...

Thanks, now i know that thing is completely useless for my purpose. Do you know any 6vAC to 12vDC transformer?

A transformer will only work with AC. Period. AC in, AC out.

An AC-to-DC converter takes AC in, the transformer reduces the incoming AC to lower voltage AC, which is rectified to pulsating DC by 1, 2 or 4 diodes, depending on the design, and smoothed by a/some filter caps to provide DC.

AC in. DC out. It doesn't work the other way.

[This is based on a linear, line frequency transformer-based supply, not a switch mode supply.]

If you feed AC into the output of an AC-DC converter, first the filter capacitors will be destroyed. After that, nothing is going to happen because the diodes block the DC from reaching the transformer.

I've explained most of this already in your several other posts.

Maybe you should do some "book learning" before randomly connecting things you don't understand together. At best, you may damage/destroy things. At worst, what you're doing could be life-threatening.

Athosworld said:

Thanks, now i know that thing is completely useless for my purpose. Do you know any 6vAC to 12vDC transformer?

Click to expand...

You just need a different rectifier configuration.
The caps have to be bigger than with a full wave bridge as each only gets recharged on alternate half cycles, also the output current is halved (but twice the voltage so around the same power).

I was once asked about a particular circuit, it was a full wave bridge rectifier with two of the diodes swapped for capacitors. After studying it for a while, I realised it was a voltage doubler as in the schematic in post #5.

Mike.

Pommie said:

I was once asked about a particular circuit, it was a full wave bridge rectifier with two of the diodes swapped for capacitors. After studying it for a while, I realised it was a voltage doubler as in the schematic in post #5.

Mike.

Click to expand...

It's funny how if you draw things 'unusually' it makes it very hard to see what it is.

I suspect he won't see anything unless he uses a DMM to measure V or R.

This assumes same N turns to the centre tap which means or 1:1 transformer , it is 50% of the voltage relative to centre tap and thus twice the current in this full wave rectifier..

Now his photo might make sense if it wasn't DC which won't work.

But if was AC to AC only power transformer with 6V output, I think he is asking the question to this answer