This Tesla coil burnout occurred when a secondary winding 20 turns from the base short circuited.
“Continue reading” for details and a video of one winding burning out on my big Tesla coil.
The winding blew out and led to primary to earth rail sparks before I shut it down. These are the big white flashes on the upper level. You can see the red hot copper which has just melted and blown apart.
Of course if it isn’t on YouTube, it didn’t happen. So here it is.
I later unwound the last 20 turns which probably were not optimal anyway and all works fine now.
This is now the fourth Tesla coil burnout I have had on this coil. Each time I have to remove a turn or two and rejoin it. It’s starting to look a little patchy now but still works fine.
This occurred during testing for a sword swallowing act.
Here is a previous one while running my Red Alert project.
It’s interesting to me how a wire that would normally handle a few amps easily will burn out in the secondary where hundreds of kV are generated at low average currents. Of course this is due to a resonant circuit where the current is effectively passing back and forth repeatedly at the 40 kHz resonant frequency.
There is a higher current at the base than at the top. But how can that be? It arises because each winding also has capacitance with respect to other windings and the ground. It cannot be regarded as a simple wire with current in equals current out despite it all being one wire.
Related pages
Sword Swallowing act.
Red Alert project
Try something else
TV German Pro Sieben (English subtitled)
External links
Photo Date: Mar 31, 2013