Abstract: Current testing/measuring apparatus 10 comprises a flexible member 12 having a first end 14 and a second end 16. In use, the flexible member 12 is arranged to locate around a conductor 11 carrying a current to be measured. In particular, the current measuring apparatus 10 comprises a Rogowski coil. The ends of the flexible member 12 are coupled together in use but a gap is created between the ends. This distance can generate errors in the current measurement and the present invention provides compensation means 28 in the form of a compensation windings. The compensation windings comprise a planar spiral conductor provided on a printed circuit board to compensate for the separation distance between the first end and the second end.

Abstract: The current measurement apparatus comprises a Rogowski coil 20 comprising a wire or conductor which forms a coil 22 and returns through the coil 22 as a central conductor. The coil 22 and the central conductor are formed from a single conductor or wire and, therefore, no electrical join (for example, a solder join or crimp) is required at the end of the Rogowski coil. The wire 28 used to form the coil 22 and the central conductor 24 is insulated prior to forming the Rogowski coil. The insulated coating 30 provides better insulation between individual coils and also helps to provide a more even spacing between the coils.

Abstract: A measuring device for detecting the state of wear of the bore walls of two interpenetrating housing bores, having mutually parallel bore axes, of at least two-shaft screw extruders has a carriage provided with rear drive wheels, front guide wheels and contactlessly operating distance sensors which can each be pivotally driven about a bore axis and can be positioned at a distance from the respective bore wall.

Abstract: A white light-emitting device using a fluorescent fiber includes a blue semiconductor light-emitting element (2) for emitting an excitation light (a), and an optical fiber (3) having one side end face and the other side end face, the excitation light (a) emitted from the blue semiconductor light-emitting element (2) being made incident to the one side end face to be guided to the other side end face. The optical fiber (3) includes a core containing therein a phosphor for emitting wavelength conversion lights by being excited by the excitation light (a) received from the blue semiconductor light-emitting element (2), and a cladding member (3B) having a light emission surface in its peripheral surface, at least a part of optically multiplexed lights, which are obtained by optically multiplexing the wavelength conversion lights and the excitation light, being emitted through the light emission surface.