I had one fail open on me, just one winding. That was after it was in use for nearly 30 years. After discovering that, I unwound it, measured the wire diameter and rewound both coils with some new wire and normal operation was restored. Mine was in an antique computer power supply. Replacements were no longer available. But the repair was simple enough. If you look at the ends of the wire carefully with a good magnifier, you might be able to see wire deformation at that ends caused by small diagonal wire cutters. Nice video, thank you for posting it.
Following your logic, I thought perhaps one of the wires was broken at the terminal... But when you measured both sides opened it got quite suspicious. I really enjoyed watching your video.. Thank you for making it !
I was troubleshooting an old Tek scope today and one of the common mode chokes in the line input filter started making noise and then emitted a bunch of smoke - part of the SMPS voltage to smoke converter phenomenon, I guess. I wasn't even taking measurements when it happened. It also blew a hole in the side of a bypass cap adjacent to it. I'm guessing the cap spontaneously shorted and took out the choke. Anyway, thanks for a great video.
That is bizarre; In all the years of servicing I have never come across a double failure in a choke. After careful consideration and looking very closely I believe it was sabotage, you can clearly see it was cut on both sides of the leg. If one side had been affected that could change my opinion, however when you consider that it slipped through quality control undetected one must wonder.
The wire was winded with tension so after a couple of months of heating/cooling cycles it just snap. Viva China! I had an ancient precision resistor bank where wires in coils break in multiple locations...
I had one fail open on me, just one winding. That was after it was in use for nearly 30 years. After discovering that, I unwound it, measured the wire diameter and rewound both coils with some new wire and normal operation was restored. Mine was in an antique computer power supply. Replacements were no longer available. But the repair was simple enough.
If you look at the ends of the wire carefully with a good magnifier, you might be able to see wire deformation at that ends caused by small diagonal wire cutters.
Nice video, thank you for posting it.
Following your logic, I thought perhaps one of the wires was broken at the terminal... But when you measured both sides opened it got quite suspicious. I really enjoyed watching your video.. Thank you for making it !
OMG, OMG, Now I need to check all my chokes!
"You! Yes, you! Stand still laddy!"
Great video. I agree with previous guesses that heat-expansion might have caused it... strange though...
I was troubleshooting an old Tek scope today and one of the common mode chokes in the line input filter started making noise and then emitted a bunch of smoke - part of the SMPS voltage to smoke converter phenomenon, I guess. I wasn't even taking measurements when it happened. It also blew a hole in the side of a bypass cap adjacent to it. I'm guessing the cap spontaneously shorted and took out the choke. Anyway, thanks for a great video.
I'd take one from an other power supply and use that. I've got a drawer full of those things all desoldered from broken power supplies.
Very well explained, thanks
looks like there's an unhappy worker at the factory ..........( soldered and cut after )
enjoyed watching and is what I was looking for thanks for sharing
Cool video, the gap does not seem to far, possible to bridge it with a jumper or huge messy blob or solder?
Awesome video..what is function of it
looks like the pins pulled out from mechanical shock.
Clever; well done
that may be a common failure since they used so much gunk, maybe something wrong with the manufacturing and later stress during assembly of the case
That is bizarre; In all the years of servicing I have never come across a double failure in a choke. After careful consideration and looking very closely I believe it was sabotage, you can clearly see it was cut on both sides of the leg. If one side had been affected that could change my opinion, however when you consider that it slipped through quality control undetected one must wonder.
you can still fix it ... a wire soldring and an good lacquer fo isolation
you have dropped it on a side, and the inertia slightly pulled out two pins out of plastic body. Must have been a good drop.
Its happed to me, cheap quality wire in the chokes.
Oh yes , I solve similar problem in 2 min last week 😀😀😀..
great
Unwrap 1 turn of wire & resolder.
He'd have to unwind all of it. The cut ends were at the start of the windings. See close-up at 4:40.
@@FlyingShotsman That sux. I would have said the same thing about unwinding a turn butttt...
In my case my transformer is gone and cant replace it
The wire was winded with tension so after a couple of months of heating/cooling cycles it just snap. Viva China! I had an ancient precision resistor bank where wires in coils break in multiple locations...
My company produces this product with fully automated equipment
huh... interesting failure point... I've seen transformer failed, but not this...
its due to heat