This application relates to methods and apparatus for monitoring power cables (100) carrying multiple AC phases to detect deformation of the power cable. A distributed fibre optic interrogator unit (302) is used to interrogate a sensing optical fibre (301) coupled to the power cable to provide a measurement signal from each of a plurality of longitudinal sensing portions of the sensing optical fibre. An analyser (602) is configured to analyse the measurements signals to detect a characteristic of an imbalance in magnetic fields. The characteristic may be a signal component with a characteristic frequency related to the power frequency and number of AC phases, the sensing optical fibre may be sensitised to magnetic fields and the characteristic frequency may be 2n times the power frequency where n is the number of phases, e.g. six times the power frequency for three phase AC.

This application relates to methods and apparatus for monitoring power cables (100) carrying multiple AC phases to detect deformation of the power cable. A distributed fibre optic interrogator unit (302) is used to interrogate a sensing optical fibre (301) coupled to the power cable to provide a measurement signal from each of a plurality of longitudinal sensing portions of the sensing optical fibre. An analyser (602) is configured to analyse the measurements signals to detect a characteristic of an imbalance in magnetic fields. The characteristic may be a signal component with a characteristic frequency related to the power frequency and number of AC phases, the sensing optical fibre may be sensitised to magnetic fields and the characteristic frequency may be 2n times the power frequency where n is the number of phases, e.g. six times the power frequency for three phase AC.

A system and method for measuring an amount of backlash in an actuator assembly that includes a housing assembly, an actuator, a drive source, an actuator position sensor, a drive source position sensor, and a controller. The controller is in operable communication with the drive source, the actuator position sensor, and the drive source position sensor, and is configured to selectively implement a built-in test that determines the amount of backlash in the actuator assembly.

A system and method for measuring an amount of backlash in an actuator assembly that includes a housing assembly, an actuator, a drive source, an actuator position sensor, a drive source position sensor, and a controller. The controller is in operable communication with the drive source, the actuator position sensor, and the drive source position sensor, and is configured to selectively implement a built-in test that determines the amount of backlash in the actuator assembly.

An example system includes a photo detector and a phase detector. The photo detector may detect a facet of a rotating mirror, the rotating mirror having at least two facets. The phase detector may detect a phase of a motor driving rotation of the rotating mirror. The example system may also include a processor to determine a phase relationship between the facet detected by the photo detector and the phase of the motor detected by the phase detector.

An example system includes a photo detector and a phase detector. The photo detector may detect a facet of a rotating mirror, the rotating mirror having at least two facets. The phase detector may detect a phase of a motor driving rotation of the rotating mirror. The example system may also include a processor to determine a phase relationship between the facet detected by the photo detector and the phase of the motor detected by the phase detector.

An electronic device, comprises: a base including a top surface and a bottom surface; a baseplate, a side edge of the baseplate is pivotally connected with the bottom surface, a moving member disposed in the base and configured to push against the baseplate; a linkage member disposed in the base and configured to push against the moving member; and a push member disposed in the base, the push member makes the baseplate moved via the linkage member and the moving member in sequence to make the baseplate selectively cover the bottom surface or detached from the bottom surface.

Provided is an encoder apparatus capable of reducing frequency of maintenance of a battery. An encoder apparatus includes: a position detection system including a detector that detects position information on a mover; an electric signal generator that generates an electric signal in response to movement of the mover; and a battery that supplies at least a part of power consumed by the position detection system in accordance with the electric signal generated by the electric signal generator.

Provided is an encoder apparatus that is free from battery maintenance or has low frequency of battery maintenance. The encoder apparatus includes: a position detection system including: a scale; a light emitter that irradiates the scale with light; a light detector that changes a relative position thereof with the scale in response to movement of a mover; and a detector that detects position information on the mover based on a detection result of the light detector. The encoder apparatus also includes an electric signal generator that generates an electric signal in response to the movement of the mover; and a light emission adjuster that adjusts emission of light from the light emitter based on the electric signal.

A rotary controller locking cap including a cap body having a longitudinal axis, a bore extending partially through the cap body along the longitudinal axis such that the cap body has an opening on a first side and is closed on an opposite second side, and an internally threaded portion arranged in the bore at least at the opening. The internally threaded portion is structured and arranged for threaded engagement with a threaded collar of a rotary controller. The bore is structured and arranged to accommodate an output shaft of the rotary controller therein while not contacting the output shaft when the cap body is engaged with the threaded collar. The cap body when engaged with the threaded collar is operable to preclude adjustability of the output shaft of the rotary controller.