Abstract: A fusion joining apparatus includes an electrical power source, a first frequency converter coupled to the electrical power source, a connector for connection to an induction fusion heater, a second frequency converter and a controller. During operation, the electrical power source generates source electrical power at a source voltage and a source frequency. The first frequency converter steps up the voltage and the frequency of the source electrical power to produce high voltage electrical power. The second frequency converter reduces the voltage and frequency of the high voltage electrical power and produces low voltage electrical power. The second frequency converter has terminals for connection to a resistance fusion heater to provide the low voltage electrical power to the resistance fusion heater.

Abstract: A method and apparatus for fusion joining polyethylene pipe. A power source supplies an input power to an input of a power supply. The input power has generally constant current and is converted to an output power at a relatively high frequency. The relatively high frequency output power is delivered to an installation tool. The output power delivered to the installation tool is controlled. The output power can be controlled as a function of ambient temperature surrounding the installation tool.