How Does A Tesla Coil Work

Easily understand how a Tesla Coil works

There are a lot of sites that try to explain how a tesla coil works, but unless your a scientist or a physics expert, these instructions are like reading Greek. I have enjoyed tesla coils for years, and own many high powered electrical devices. After seeing the obscure docs on the internet, I have created a very easy to understand diagram and fact sheet on 'How tesla coils work'.

TRANSFORMER - Takes 110 volt wall socket current, and steps it up to several thousand volts (depending on the transformer).
CAPACITOR - Acts like a battery, and takes the stepped-up voltage and stores it until it's fully charged. Once fully charged, the SPARK-GAP fires, releasing all of the capacitors stored energy in a sngle powerful burst or pulse.
SPARK-GAP - From the SPARK-GAP, the current flows to the large PRIMARY COIL.
PRIMARY COIL - The PRIMARY COIL, is usually made from thick copper wire or even pipe, consisting of 5-25 turns or coils. This large copper coil produces a strong magntic field as the current flows through it, the current is then picked up by the SECONDARY COIL.
SECONDARY COIL - This SECONDARY COIL, acts like another transformer, and consists of numerous turns or coils of smaller gauge copper wire. Here the current continues building by the effects of the magnetic field on the copper, until it reaches massive voltage levels. This current moves up into the DISCHARGE SPHERE.
DISCHARGE SPHERE - The DISCHARGE SPHERE also acts like a simple capacitor (storage battery), before discharging the current as sparks and corona.

Take a Look at My Tesla Coils and other High Voltage Devices

110 KV Spark Gap Tesla Coil

120 Volt - 60 Hz Input. Drive Transformer is open frame 4 KV Neon Sign Type with twin bobbin windings. The HV Secondary of the transformer is not connected to ground. The power ground and bottom of the tesla coil secondary are connected on the base using a brass terminal post. The Discharge Wand connects to the grounded brass terminal post. The secondary is machine wound with #26 AWG HPN (Heavy Poly-Nylon)insulated wire and coated with several coats of clear enamel. The capacitor is a 0.001 MFD AEROVOX Mica Transmitter Type rated at 12,500 Volts. The Spark Gap is brass and adjustable.

110 KV Bipolar Spark Gap Type Tesla Coil

120 Volt 60 Hz input. Drive transformer is 4,000 Volt Open Frame Neon type. The capacitor is 1400pF 20kV rated Door Knob Type manufactured by Murata. The Secondary is machine wound with #26 AWG HPN (Heavy Poly-Nylon) insulated and has several coats of clear enamel. The Spark Gap is brass and adjustable. The line ground is brought out on a Brass Terminal Post on the front of the wood housing.
Bipolar Tesla Coil

400 KV Van de Graaf Generator

This Van de Graaf Generator can discharge up to 18 inch spark depending upon humidity levels. If you grab the side of the tower about 10 inches down from the dome you will see a 4 inch wide rippling stream of electrons following to your hand. Take off the dome where you will see and hear the hiss of electrons discharging to the copper combs. Insulate yourself while touching the dome, then point your finder to watch it glow blue from piercing electric field or just back up and allow yourself to get zapped with about 400,000 volts! And if you like the arcs, you will love the feeling of a hair standing 400,000 volt static electric field.

Dimensions: 3 feet 2 inches tall - 15 inch stainless steel discharge sphere - 2.25 inch wide belt - 2ft internal belt chamber - 3600 rpm belt driven motor - Flanged sealed bearings - Top roller (2.8” wide) - Bottom roller (2.8” wide) - External Speed Control - 18 inch arcs

High Frequency Generator - Odin Coil

This high-frequency transformer can step up ordinary 110-volt electricity to fifty thousand volts. Create impressive 3-inch sparks or use the high potential to light bulbs such as spectrum tubes or a Neon Wand, without touching! Adjustable from 10,000 to 50,000 volts.

Wimhurst Machine

The Wimshurst Machine consists of two glass or plexiglass plates revolving in opposite directions. On the outside of each of these plates are cemented a number of tinfoil "sectors," arranged radially. Two conductors at right angles to each other extend obliquely across the plates, one at the back and the other at the front. These conductors each terminate in brushes of tinsel which electrically excite the "sectors" as the plates revolve. The electricity is coll ected by a set of "collectors".

Homemade Capacitor - Leyden Jar

You only need an empty pill bottle or a film cannister with lid, and some wire, a screw, aluminum foil and tape, to make a nice high voltage capacitor - leyden jar. You can charge the leyden jar by simply holding it near a van de graff generator or wimhurst machine, or by rubbing the braided wire slightly across the tv screen, when static has accumlated. Discharge the leyden jar by toughing the single strande discharge wire to the top screw.

Large 300,000 Volt Tesla Coil

20"+ electrical arcs at over 150 breaks per second - -Commercial grade 4kv 60 ma non-gfi transformer - 12,000 volt, .047 mfd MMC capacitor bank - 14" x3.5” high inductance secondary coil, tightly wound with heavily insulated magnet wire - Pure copper spiral primary coil - Air-cooled multi-quenching static gap with pure copper electrodes - 12” aluminium composite discharge toroid with brass breakout rod - Estimated output voltage of 300,000 volts

I hope you enjoyed the easy to understand article on Tesla Coil operation, and had fun looking at the Tesla Coils and other high voltage devices. All of the Tesla Coils, and other items on this page, are owned by me. I will be posting new pictures, whenever I purchase a new electrical device. Check back often for updates. This site was last updated: (Sep. 11. 2008)
Sincerely,
Robert W. Benjamin

This website is dedicated to the Genius Nikola Tesla (1856-1943)- 'I would of enjoyed working with him'