Electric Fail , Explosion, High Voltage, Fire, Jacob's Ladder

An electric arc or arc discharge is an electrical breakdown of a gas that produces an ongoing electrical discharge. The current through a normally nonconductive medium such as air produces a plasma; the plasma may produce visible light. An arc discharge is characterized by a lower voltage than a glow discharge, and it relies on thermionic emission of electrons from the electrodes supporting the arc. An archaic term is voltaic arc, as used in the phrase "voltaic arc lamp".

With the microwave oven transformer, a simple electrical circuit can be rigged to get high voltage arcs to fly outward and upward along a "V" shaped spark gap.

You can look, but don't touch! These arcs of plasma are lethal enough to kill on contact!

TheMOT looks like a large metal cube, and is very heavy.

There are 2 sets of copper coils. A primary coil (the bottom one here), which connects to your house power, and the secondary coil, which generates the high voltage to run your microwave. By tapping one end of the secondary to the transformer body, the circuit is completed, and a large amount of electric current jumps the gap.

REAL DANGER! When playing with high voltage (HV), it's important to keep your distance. When the power was on, I used an insulated stick, gloves, and also kept one hand behind my back at all times.

A diverging spark gap can easily be made with a metal coat hanger, or a couple pieces of un-insulated copper wire. WITH THE POWER OFF, the secondary coil is connected to the spark-gap, then with power back on, the spark is introduced. As the spark heats the air, the air rises, taking the arc with it.

The hum of the 60Hz arc dissipates as it breaks off the top. A smaller spark gap can capture a glowing orb of plasma, and when a HV capacitor is placed in parallel, the sparks are sharp, powerful, and loud. They even change in color from yellowish green, to a crisp bright blue.
It can't be stated enough that this amount of power needs to be treated with extreme caution and respect. One wrong move could be your last one.

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