Abstract: A testing system includes a truck carrying a circuit breaker, a fixed contact, and an actuator piston connected to a movable contact. A test platform supports the truck in a contact testing position and includes a sensor circuit mounted on the test platform and positioned under the truck and aligned with the circuit breaker when the truck is on the test platform in the contact testing position. The sensor circuit is configured to acquire displacement data of the actuator piston when the movable electrical contact is moved between the open and closed positions. A controller is coupled to the sensor circuit and configured to receive the displacement data and determine electrical contact erosion within the circuit breaker.

Abstract: A switchgear system includes a switchgear frame and a truck carrying a circuit breaker, which includes a breaker housing, a fixed electrical contact and a movable electrical contact mounted within the breaker housing, an actuator piston connected to the movable electrical contact, and a drive assembly coupled to the actuator piston. A sensor circuit is mounted on the switchgear frame under the truck and aligned with the circuit breaker and configured to acquire displacement data of the actuator piston when in a contact testing position. A controller is coupled to the sensor circuit and configured to receive the displacement data and determine electrical contact erosion within the circuit breaker.

Abstract: A testing system includes a truck carrying a circuit breaker, a fixed contact, and an actuator piston connected to a movable contact. A test platform supports the truck in a contact testing position and includes a sensor circuit mounted on the test platform and positioned under the truck and aligned with the circuit breaker when the truck is on the test platform in the contact testing position. The sensor circuit is configured to acquire displacement data of the actuator piston when the movable electrical contact is moved between the open and closed positions. A controller is coupled to the sensor circuit and configured to receive the displacement data and determine electrical contact erosion within the circuit breaker.

Abstract: A switchgear system includes a switchgear frame and a truck carrying a circuit breaker, which includes a breaker housing, a fixed electrical contact and a movable electrical contact mounted within the breaker housing, an actuator piston connected to the movable electrical contact, and a drive assembly coupled to the actuator piston. A sensor circuit is mounted on the switchgear frame under the truck and aligned with the circuit breaker and configured to acquire displacement data of the actuator piston when in a contact testing position. A controller is coupled to the sensor circuit and configured to receive the displacement data and determine electrical contact erosion within the circuit breaker.

Abstract: A testing system includes a truck carrying a circuit breaker, a fixed contact, and an actuator piston connected to a movable contact. A test platform supports the truck in a contact testing position and includes a sensor circuit mounted on the test platform and positioned under the truck and aligned with the circuit breaker when the truck is on the test platform in the contact testing position. The sensor circuit is configured to acquire displacement data of the actuator piston when the movable electrical contact is moved between the open and closed positions. A controller is coupled to the sensor circuit and configured to receive the displacement data and determine electrical contact erosion within the circuit breaker.

Abstract: A switchgear system includes a switchgear frame and a truck carrying a circuit breaker, which includes a breaker housing, a fixed electrical contact and a movable electrical contact mounted within the breaker housing, an actuator piston connected to the movable electrical contact, and a drive assembly coupled to the actuator piston. A sensor circuit is mounted on the switchgear frame under the truck and aligned with the circuit breaker and configured to acquire displacement data of the actuator piston when in a contact testing position. A controller is coupled to the sensor circuit and configured to receive the displacement data and determine electrical contact erosion within the circuit breaker.

Abstract: A switchgear system includes a switchgear frame and a truck carrying a circuit breaker, which includes a breaker housing, a fixed electrical contact and a movable electrical contact mounted within the breaker housing, an actuator piston connected to the movable electrical contact, and a drive assembly coupled to the actuator piston. A sensor circuit is mounted on the switchgear frame under the truck and aligned with the circuit breaker and configured to acquire displacement data of the actuator piston when in a contact testing position. A controller is coupled to the sensor circuit and configured to receive the displacement data and determine electrical contact erosion within the circuit breaker.

Abstract: A testing system includes a truck carrying a circuit breaker, a fixed contact, and an actuator piston connected to a movable contact. A test platform supports the truck in a contact testing position and includes a sensor circuit mounted on the test platform and positioned under the truck and aligned with the circuit breaker when the truck is on the test platform in the contact testing position. The sensor circuit is configured to acquire displacement data of the actuator piston when the movable electrical contact is moved between the open and closed positions. A controller is coupled to the sensor circuit and configured to receive the displacement data and determine electrical contact erosion within the circuit breaker.

Abstract: An acoustic testing system includes at least four control microphones, at least four acoustic transducers, an acoustic enclosure with pre-determined reverberant characteristics which contains the at least four control microphones and the at least four acoustic transducers, a control system configured to produce a predetermined acoustic field as measured by the at least one control microphone. A unit under test is also disposed within the acoustic enclosure. Using an acoustic enclosure with pre-determined reverberant characteristics results of the increased proportion of reflected sounds in the area proximate to the unit under test such that less power is required to achieve a given acoustic test level than in a purely direct field acoustic test.

Abstract: A direct field acoustic testing system includes at least two acoustical transducer groups and a signal modifier for introducing separately controllable time delays or phase shifts for each acoustical transducer group so as to provide an acoustic field conforming to a pre-determined specification with reduced deviations due to constructive or destructive interference between the acoustical transducer groups.

Abstract: An acoustic testing system includes at least four control microphones, at least four acoustic transducers, an acoustic enclosure with pre-determined reverberant characteristics which contains the at least four control microphones and the at least four acoustic transducers, a control system configured to produce a predetermined acoustic field as measured by the at least one control microphone. A unit under test is also disposed within the acoustic enclosure. Using an acoustic enclosure with pre-determined reverberant characteristics results of the increased proportion of reflected sounds in the area proximate to the unit under test such that less power is required to achieve a given acoustic test level than in a purely direct field acoustic test.

Abstract: A direct field acoustic testing system includes at least two acoustical transducer groups and a signal modifier for introducing separately controllable time delays or phase shifts for each acoustical transducer group so as to provide an acoustic field conforming to a pre-determined specification with reduced deviations due to constructive or destructive interference between the acoustical transducer groups.

Abstract: A compact audio reproduction system for two input signals includes at least four loudspeakers disposed at the vertices of a quadrilateral not more than two feet on any side and such that no two loudspeakers are located at a distance from one another which is less than one-fourth the greatest distance between any two loudspeakers. The two input signals are connected to alternate speakers such that no two loudspeakers at adjacent vertices of the quadrilateral produce the same signal such that a listener at an arbitrary location perceives a sound source larger than the quadrilateral and significant stereo image. The signals received by two loudspeakers located at adjacent vertices may receive signals which are equalized separately from the signals received by the other loudspeakers for the purpose of reducing comb filtering and improving the tolerance of the device to placement near walls and other obstructions.

Abstract: In a loudspeaker system with main and sub-speakers, a modified and inverted left surround signal is added to the signals driving the right main speaker and a modified and inverted right surround signal is added to the signals driving the Left Main Speaker for the purpose of creating more credible rear located phantom sound images. In a system using variations of a difference signal to create phantom rear located sound images, the components of the difference signal are modified by introducing a time delay to one of the components for the purpose of preventing the components of the difference signal from substantially canceling each other. The components of the difference signal may be modified by altering the relative level and frequency response of the components for the purpose of preventing the components of the difference signal from substantially canceling each other.

Abstract: A surround sound reproduction system uses a series of filters and a system of main and sub-speakers to produce phantom rear surround sound channels or a phantom surround sound effect from a loudspeaker system or pair of loudspeaker systems located in front of the listener. The sound system includes left and right surround input signals, and left and right front input signals. Left and right sub-speakers, and left and right main speakers are located in front of a listening location. Spacing between respective main and sub-speakers is approximately equal to ear spacing for an average person. The input to the left sub-speaker comprises the right surround signal subtracted from the left surround signal each signal having previously passed through a front-to-back filter and a series of high and low pass filters. The input into the left main speaker comprises the left front signal added to the left surround signal after the left surround signal has passed through a front-to-back filter.

Abstract: A port for a loudspeaker is disclosed which is sufficiently weather resistant for long term outdoor use and which prevents debris, insects and other vermin from entering the loudspeaker and which is compact and efficient.