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Building a fusion reactor (part 5): transformer arc test

Updated: Mar 31

The first major step in creating our high voltage system was making sure our transformer was working safely. To do this, we decided to perform an arc test. The transformer we used was a 12KV 30ma neon-sign transformer which are inherently current-limited, making them safer than other types.

First, we made the power supply by stripping an extension cord, and attaching heat shrinks and O-rings at the ends. This way the cord is insulated, color coded, grounded, and sturdy.

Next, we had to create a grounding stick, or as some may know it as the “Jesus” stick (the word you say when you don’t use it). This stick is just a way to draw an arc by connecting a grounded conductor to one of the outputs. To do this, I stripped a few inches of THHN wire, whose inside is one thick strand of copper which is sturdy and nonbendy. This was soldered to standard bendy high-voltage wire, thus acting as a prod at the end of the wire. Finally, we attached this wire to some PEX piping using heat shrinks and added an O-ring to the other end. What we are left with is a stick that basically has a long stick of wire.

The tables in our physics room are magnetic, disrupting the field created in transformers so we placed an insulating yoga mat under the transformer. After connecting the power cord to the transformer and connecting the grounding stick to the ground wire in the transformer, we were able to draw a half-inch arm from both terminals of the transformer. These arcs are relatively wide but don’t stretch far, which is a good sign as a long stretch distance of an arc is often an indicator of high current while fatter arcs are a sign of higher voltages.



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