Abstract: The invention provides a method and apparatus for determining the complex impedance of an electrical component. The method comprises the steps of applying an input signal to the component comprising a plurality of discrete frequencies simultaneously, and determining the complex impedance of the component at each of the frequencies using a discrete demodulation technique on two complex impedance related parameters at each of the discrete frequencies. This method is particularly useful in electrically noisy environments and can be used to determine the impedance and equivalent circuit parameters for a battery. It can also be applied to battery system interconnects to enable battery system currents to be determined.

Abstract: A corrona test set has at least a reactor and power separation filter placed in an oil-filled conductive tank of a conductive material such as sheet steel. The exciter optionally may also be placed in the same tank enclosure which is of much smaller size than the equivalent voltage rating test set in air. High voltage taken from the circuit passes out of the tank through high voltage bushings. A preferred form of bushing is a quick coupling cable receiving device having an insulator extending into the tank and a frustoconical metallic extension extending away from the tank with a tubular internal wall connected to these respective parts at opposite ends to form a further oil-filled compartment separate from the tank.

Abstract: A testing apparatus for testing electrical insulation, such as cable insulation or electrical rotating machinery ground wall insulation, whereby a cyclically variable inductive reactor is connected in series with an ac power source and the test specimen. The inductance of the reactor is continuously varied such that the magnitude of the inductance is a periodic function of time. As a result the voltage applied to the insulation of the test specimen is in the form of modulated line frequency oscillations passing through resonance.

Abstract: A corrona test set has at least a reactor and power separation filter placed in an oil-filled conductive tank of a conductive material such as sheet steel. The exciter optionally may also be placed in the same tank enclosure which is of much smaller size than the equivalent voltage rating rest set in air. High voltage taken from the circuit passes out of the tank through high voltage bushings. A preferred form of bushing is a quick coupling cable receiving device having an insulator extending into the tank and a frustoconical metallic extension extending away from the tank with a tubular internal wall connected to these respective parts at opposite ends to form a further oil-filled compartment separate from the tank.

Abstract: A corrona test set has at least a reactor and power separation filter placed in an oil-filled conductive tank of a conductive material such as sheet steel. The exciter optionally may also be placed in the same tank enclosure which is of much smaller size than the equivalent voltage rating test set in air. High voltage taken from the circuit passes out of the tank through high voltage bushings. A preferred form of bushing is a quick coupling cable receiving device having an insulator extending into the tank and a frustoconical metallic extension extending away from the tank with a tubular internal wall connected to these respective parts at opposite ends to form a further oil-filled compartment separate from the tank.

Abstract: Location of a fault in electrical conductors from a terminal position which may be remote from the fault using at least a broad band pulse generator to generate a pulse at a terminal position. It also uses a voltage source at the terminal position capable of inducing a change of impedance at the fault and time measuring means also at the terminal position. The method involves generating a first pulse at the terminal position which is propagated down the conductor and reflected back to the terminal position from various impedance discontinuities, including the impedance discontinuity of the fault, if present. The pattern of reflections from points along the conductor up to the fault resulting from the first pulse are recorded. Then sufficient voltage is applied to the cable to induce a change in impedance at the fault.

Abstract: Grounding of poles in a power distribution system is checked by disconnection of the ground wire from the buried grounding conductor (rod) and measurement of the reference ground by conventional techniques. If necessary the grounding conductor is enlarged to lower ground resistance to an acceptable level between 5 and 10 ohms. A pulse generator is then connected between the grounding conductor and the ground lead at the reference pole to generate and transmit through the system netural wire a pulse, preferably on the order of 5 kHz to simulate lightning strikes on the systme neutral. Adjacent poles are then checked one at a time using a current type pickup with peak detector equipment. It is necessary to disconnect the ground wire from the ground connector. A first value is obtained by checking the effects of a pulse in the neutral wire of the distribution system adjacent the selected pole and the output is adjusted by a potentiometer to read 100.