I am tempted to make a sock puppet account just to avoid having this idiocy forever tied to me, but ah well.
I have a 50va 2x115:2x12v Noratel toroid transformer that I clearly wired wrong. It took me some time to figure out that while I was not getting the meter readings I expected, the transformer was busily getting itself very hot.
So of course I panicked and pulled all the wires and can't see precisely how I had it connected. What I want is to get 24 volts out of it, so I tried to connect the secondaries in series.
Primary: blue (dot) - grey, violet (dot) - brown.
These I connected brown to grey, violet to blue.
Secondary: black (dot) - red, orange (dot) - yellow
These it looks like I connected orange to red, then took the power from black and yellow. But I'm guessing based on tape residue.
Naturally my confidence has been shaken since, but it's been a few days and I have a hankering to do some soldering. I would really appreciate any advice anyone can offer.
Thanks!
I have a 50va 2x115:2x12v Noratel toroid transformer that I clearly wired wrong. It took me some time to figure out that while I was not getting the meter readings I expected, the transformer was busily getting itself very hot.
So of course I panicked and pulled all the wires and can't see precisely how I had it connected. What I want is to get 24 volts out of it, so I tried to connect the secondaries in series.
Primary: blue (dot) - grey, violet (dot) - brown.
These I connected brown to grey, violet to blue.
Secondary: black (dot) - red, orange (dot) - yellow
These it looks like I connected orange to red, then took the power from black and yellow. But I'm guessing based on tape residue.
Naturally my confidence has been shaken since, but it's been a few days and I have a hankering to do some soldering. I would really appreciate any advice anyone can offer.
Thanks!
your primary connection is okey (if your mains are 115V).
Your secondary wireing would be black and yellow tied together or red and orange. And then connected to 0V for 12-0-12V or just insulate the connection for a single 24VAC.
Your secondary wireing would be black and yellow tied together or red and orange. And then connected to 0V for 12-0-12V or just insulate the connection for a single 24VAC.
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Now I feel really stupid, because I don't see the difference between what you are suggesting and what I did. I guess I will try it again.
it's no difference 🙂 but since you are not sure, i stated the way it should be.
just to make sure. your mains are 115V? not 230V?
just to make sure. your mains are 115V? not 230V?
Yes they are 115v. I have just inspected the power supply board in case I soldered something backwards or made an obvious short, but I do not see any. Still, I am very nervous to try this again.
No, there was nothing connected to the dc out on the board. The transformer secondaries were connected to the AC inputs. Was that a bad idea?
then the transformer was connected to something. atleast a rectifier and caps.
just trying to figure out where the foult is. try the transformer alone. don't connect the secondaries to anything. just don't short it out 🙂
before fireing up the transformer, measure resistance of each primary windings and each secondaries windings.
just trying to figure out where the foult is. try the transformer alone. don't connect the secondaries to anything. just don't short it out 🙂
before fireing up the transformer, measure resistance of each primary windings and each secondaries windings.
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Ok thanks so much for your help. I'll try it again later once I'm not the only adult looking after my boy just in case.
With brown-grey and violet-blue, I see 14 ohms across the joined pairs.
With brown, grey, violet and blue separated, I see 24.9 ohms across brown and violet, and 25 ohms across grey and blue.
With orange-red, I see 1.1 ohms across yellow and black.
With orange and red separated, I see .7 ohms across orange and yellow, and 0.7 ohms across black and red.
To me, it still looks like I hooked it up right. So by process of elimination, I screwed up putting the board together. Or I should pick another hobby...
With brown, grey, violet and blue separated, I see 24.9 ohms across brown and violet, and 25 ohms across grey and blue.
With orange-red, I see 1.1 ohms across yellow and black.
With orange and red separated, I see .7 ohms across orange and yellow, and 0.7 ohms across black and red.
To me, it still looks like I hooked it up right. So by process of elimination, I screwed up putting the board together. Or I should pick another hobby...
Of course it's possible I put it all together properly, but I blew something up because I selected the wrong transformer. This is a Glassware LV-Regulator kit, which I am using in a full wave bridge configuration. It uses an LD1085 and the instructions say to not expose it to a voltage differential of 30v.
24 rectifies to 34 volts, and I want 12 volts out, so I figured that's a differential of 22 volts or so. But maybe that's not what it means, and something is toast because of it.
24 rectifies to 34 volts, and I want 12 volts out, so I figured that's a differential of 22 volts or so. But maybe that's not what it means, and something is toast because of it.
i do not know this kit, or the regulator itself.
EDIT: Datesheet say absolute maximum input voltage 30VDC.
EDIT: Datesheet say absolute maximum input voltage 30VDC.
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Aha I can see how pushing too much voltage through the regulator could short it out, and that would cause the transformer to heat up as it's just dumping current into a short, is that what probably happened?
Thank you so much for your help, this has been enlightening.
Thank you so much for your help, this has been enlightening.
If everything worked first time:
1/ That would be boring.
2/ You didn't learn anything from your mistake(s).
As long as I'm admitting to being stupid here, I may as well add that no, I wasn't using a fuse, and yes, I will use a fuse before I work with mains wiring again.
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