This type of high-voltage transformer employs an adjustable output current limiter and is suitable for use in Multiple Wave Oscillators, Tesla transformers and similar types of devices.
Technical Specifications
Primary
Input voltage: 110 – 250 V as requested (several taps provided for output voltage selection)
Secondary
Output voltage: 1 – 20 kV as requested
Output current: as requested (total secondary power up to 900 W)
Output current limiting range: ~25 – 100 %
Dimensions (LxWxH)
240 x 200 x 190 (120) mm
Weight
15 – 17 kg (depends on requested specifications)
Description
The high voltage transformer is built on a custom-made, high-quality transformer steel core rated at 1 kW. The primary and secondary windings are physically separated to improve mutual primary-to-secondary insulation, and individual layers of secondary windings are additionally insulated with sheets of Mylar. To increase safety in the unlikely event of insulation breakdown, the secondary windings have a centre tap connected to the transformer steel core and usually grounded.
Secondary windings can be wound to virtually any requested output voltage/current combination up to 800–900 W. Additional taps on the primary windings provide different voltage ratios, so different output voltages are available to the user, eliminating the need for an adjustable input transformer (VARIAC).
Apart from the adjustable laser-cut core used for output current limiting, the entire transformer is cast in high-voltage polyurethane (45 kV/mm), then vacuumed to remove remaining air bubbles, after which it is cured in a high-temperature oven.
The entire transformer weighs 15–17 kg and can be mounted inside enclosures using large embedded threaded nuts.
The current-limiter adjustment mechanism is custom-machined and mounted on the finished transformer. The adjustment mechanism moves the precision-cut magnetic shunt in and out of the transformer core, limiting output current with virtually no effect on output voltage. Because it uses Teflon sliders, the current-limiter magnetic shunt produces barely audible noise and hum during operation while providing current adjustment from ~25–100% of output current.
