Another way in which a high voltage is determined is if there are any insulation requirements specific to the voltage.
The global organization of the International Electrotechnical Commission, as well as its national counterparts (such as the American National Standards Institute) classifies a high voltage as being one thousand volts for an alternating current circuit and fifteen hundred volts for a direct current circuit.
Although they are held to fairly strict standards, high voltage coils are utilized in a broad spectrum of industries including the medical field, where devices such as cathode ray tubes generate X-rays for medical imaging applications. The power generation industry uses these electrical coils for applications such as electrical power distribution.
Automotive manufacturers employ high voltage coils as ignition coils in vehicles such as cars, trucks, vans and sport utility vehicles. Also, industrial manufacturing utilizes them for power generation to warehouses as well as equipment and for measurement and testing applications such as with photomultiplier tubes.
There are two main types of high voltage coils: ignition coils and Tesla coils. Much more common for industrial applications, ignition coils serve to fire up the spark plugs by means transforming the current flow from the vehicle’s battery (typically a twelve volt or a six volt) into the high voltage (from twenty thousand to thirty thousand volts) that is required by the spark plugs.
An ignition coil consists of a core and a primary and a secondary wound wire. The primary wire is generally formed from a heavy gauge of copper that is insulated in protective materials like encapsulated coils, and contains about one hundred to one hundred and fifty turns, or coils of wire. Conversely, the secondary coil is typically formed from a fine gauge of copper, which must also be insulated and contains many more turns, generally ranging from fifteen thousand to thirty thousand turns.
More common for entertainment and educational purposes, a Tesla coil, on the other hand, has been around since 1891 and is a type of resonant transformer circuit. A Tesla coil can be used to produce not only a high voltage of electricity, but also a fairly high current, and frequency. Using alternating current flow, Tesla coils are often utilized in order to produce long sparks of electricity.
High voltage coils are also utilized in high voltage power transformers in order to handle elevated amounts of electrical energy in the range of six hundred to five thousand volts.