Abstract: A spark fault tester apparatus includes an electrode; a power supply operatively connected to provide an electrical field at the electrode; a voltage monitoring module operatively connected to measure the intensity of the electrical field at the electrode; a current monitoring module operatively connected to measure a current output of the power supply; and a microprocessor operatively connected to sample the voltage monitoring module and the current monitoring module, and to adjust the power supply. The microprocessor implements a voltage regulation algorithm and a fault typing algorithm, based on samples of the voltage and current monitoring modules, to distinguish among at least two types of insulation defects.

Abstract: A spark tester electrode includes a first bracket that supports a first plurality of filaments and a second bracket that supports a second plurality of filaments. The first and second brackets are mutually disposed at angles toward each other, such that the first plurality of filaments that are supported from the first bracket intermingle with the second plurality of filaments that are supported from the second bracket.

Abstract: Detection of a coating defect on a catheter shaft, by imposing AC voltage between an electrode and a grounding tube, passing the catheter shaft through the grounding tube and through the hole of the electrode, monitoring the voltage between the electrode and the grounding tube, and detecting the coating defect, in case the amplitude of the monitored voltage drops below a threshold value. The electrode defines a hole, which opens from an infeed side of the electrode to an outfeed side of the electrode. A voltage supply provides the AC between the electrode and system ground. A fault detection circuit monitors the electrode. The grounding tube has an outer surface connected to system ground, and is coaxial with the electrode hole, an inward tube end proximate the hole and an outward tube end distal the hole.

Abstract: A system and method for high voltage testing of twisted insulated conductors includes a high voltage power supply to be disposed within a rotating mechanism of a twinner. An electrode is coupled to the power supply and is to be disposed adjacent to a take-up reel within the rotating mechanism of the twinner. The electrode is for generating sparks between the electrode and the twisted insulated conductors when a fault in the insulation of the twisted conductors, when being wound on the take-up reel, passes by the electrode. A transmitter is to be disposed within the rotating mechanism for transmitting a signal carrying information representative of fault detection characteristics of the twisted insulated conductors. The information is derived from the sparks generated between the electrode and the twisted insulated conductors. A receiver is to be disposed outside of the rotating mechanism for receiving the signal from the transmitter.

Abstract: A system and method for high voltage testing of twisted insulated conductors includes a high voltage power supply to be disposed within a rotating mechanism of a twinner. An electrode is coupled to the power supply and is to be disposed adjacent to a take-up reel within the rotating mechanism of the twinner. The electrode is for generating sparks between the electrode and the twisted insulated conductors when a fault in the insulation of the twisted conductors, when being wound on the take-up reel, passes by the electrode. A transmitter is to be disposed within the rotating mechanism for transmitting a signal carrying information representative of fault detection characteristics of the twisted insulated conductors. The information is derived from the sparks generated between the electrode and the twisted insulated conductors. A receiver is to be disposed outside of the rotating mechanism for receiving the signal from the transmitter.

Abstract: A variable inductance transformer includes a core defining a gap between opposing first and second ends. A primary winding and at least one secondary winding are coupled to the core. The secondary winding is provided for stepping up the voltage across the primary winding. A carriage assembly includes a magnetic shunt movable against the core and variably across the gap. The magnetic shunt has a width at least as wide as the gap for moving the shunt to a predetermined position along the core in a range from an uncovered position not overhanging the gap, throught intermediate positions overhanging the gap, to a covered position where the shunt bridges the gap. A control circuit controllably energized a motor to move the carrriage assembly and position the magnetic shunt against the core for adjustably varying the inductance of the secondary winding a to maintain a high output voltage of the transformer for a given resistive supply current.

Abstract: An apparatus for testing the insulation of an insulated electrical conductor has an alternating current high voltage power source which provides a high test voltage between the electrical conductor and an electrode to reveal defects in the insulation. A high Q antiresonant circuit, tuned to a predetermined frequency, is connected in series with the electrode and power source for shunting most frequency components of the corona and noise currents to ground and for non-shunting an insulation fault voltage of the predetermined frequency resulting from an arc current due to a defect in the insulation. The fault voltage signal non-shunted by the antiresonant circuit is provided through a coupling impedance to a transmission cable having a pair of twisted wires for transmission to a remote location. Impedance matching transformers, coupled to both pairs of ends of the twisted wires, are tuned to the same frequency as the antiresonant circuit to minimize attenuation of the signal.

Abstract: Apparatus for testing the insulation on an insulated conductor wherein a high AC test voltage is applied to an electrode through which the insulated conductor is passing is presented and includes a testing station for applying the high AC test voltage potential to an electrode at a desired magnitude and frequency. Current induced in the electrode due to corona effects or arc current pulses due to a defect in the insulation are sensed by a current sensing transformed circuit to develop a insulation condition voltage signal. The insulation condition voltage signal together with a low voltage test signal proportional to the magnitude of the high AC test voltage potential are coupled to a remotely located controlled unit. A negative peak detector receives the low voltage potential to produce a bias voltage at the input to the fault detection circuit.

Abstract: A remotely controlled high potential dc insulation tester includes a dc power supply and a high voltage electrode mounted within a rotating mechanism and performs insulation tests on conductors which are within the same rotating mechanism. The power supply receives low voltage electrical power from outside of the rotating mechanism, and is monitored and controlled from a remote station in a non-rotating environment. Detecting circuits at the remote station determine the number of faults in a conductor drawn past the electrode and identify large faults such as bare-wire intervals along the conductor.