High Voltage, Inc. is an American test equipment manufacturing company located in rural Copake, New York. The company’s HPA line of ac testers are available with outputs up to 300 kV ac and power levels up to 40 kVA and can be customized with various levels of control sophistication. The company’s new PAR line of ac dielectric testers are designed to meet the needs of those who need power levels up to 250 kVA, to be able to test their highly capacitive test loads. Using ac resonant technology outputs of 50 kV at 5A (for example) are possible with an input of only 230 v, 90 A. That is an input of 20 kVA for an output of 250 kVA. (Model PAR-50250FC5)
The PAR models consist of a control section and a high voltage section. While large, they are transportable by van or trailer for field work. The control section includes the input breaker, variable (motorized) input control, a PLC controller, and connections for controlling the hv section. The high-voltage section is a steel tank with a phenolic output bushing. Inside this tank is a variable-core reactor in an insulating oil bath with an air space at the top to allow for thermal expansion. The variable reactor looks similar to a transformer but has a moveable core that allows the inductance value to vary to match the capacitance of the load, thereby achieving resonance. This effectively cancels the load capacitance, as far as input power requirements are concerned. Once in resonance, the input voltage is increased until the desired output voltage level is achieved. For a capacitive load that must be tested at power frequency the PAR reduces power requirements, as well as test equipment size by one tenth to one thirtieth, compared to a test transformer.
The HVI PAR family of resonant as dielectric testers are suitable for power frequency testing of power cables, rotating machinery, bushings, instrument transformers, transformers, shunt reactors, and many other products.
High Voltage, Inc. | www.hvinc.com
Booth #5831
