Abstract: The device for the impedance-based probing of materials described herein comprises a two-dimensional array of coils (1) and a measurement unit (4) adapted to determine, for each coil (1), a parameter indicative of its impedance. A pulse generator (3) is able to generate current pulses in each coil (1). The circuitry drives and senses the coil array through row and column lines (rp1 . . . rpN1, cp1 . . . cpN2, c21 . . . csN2) in order to minimize the number of required components. The device can, in particular, be used for probing concrete.

Abstract: The device for the impedance-based probing of materials described herein comprises a two-dimensional array of coils (1) and a measurement unit (4) adapted to determine, for each coil (1), a parameter indicative of its impedance. A pulse generator (3) is able to generate current pulses in each coil (1). The circuitry drives and senses the coil array through row and column lines (rp1 . . . rpN1, cp1 . . . cpN2, c21 . . . csN2) in order to minimize the number of required components. The device can, in particular, be used for probing concrete.

Abstract: Device for determining wear in a carbon ceramic brake disk. The device includes a coil arrangement having at least one coil structured and arranged to generate a magnetic field in the brake disk and to detect an eddy current in the brake disk, and an arcuate measuring area.

Abstract: Device for determining wear in a carbon ceramic brake disk. The device includes a coil arrangement having at least one coil structured and arranged to generate a magnetic field in the brake disk and to detect an eddy current in the brake disk, and an arcuate measuring area.

Abstract: An intrusion detector has a housing with an infrared device disposed therein, an infrared sensor, a detector window provided in the housing wall for the passage of infrared radiation from the external space onto the infrared sensor, an element for focusing the infrared radiation incident through the detector window onto the infrared sensor and having a sabotage surveillance device including an infrared transmitter and an infrared receiver. The infrared transmitter and the infrared receiver are disposed inside the housing and the detector window is substantially transparent to radiation emitted by the infrared transmitter. The sabotage surveillance of the detector takes place by measuring the proportion of the radiation reflected onto the infrared receiver from the inside of the detector window and the radiation transmitted onto the infrared receiver from the surrounding space.

Abstract: A serial data bus with a two-wire line and a plurality of bus nodes for the exchange of data messages in both directions between the bus nodes and a central unit connected to the bus and for the current supply of the bus nodes. Conflicts between data messages that appear simultaneously are resolved on the basis of the priority thereof. The bus is constructed in the manner of a multi-master system in which each bus and the central unit is a master, and the central unit provides the bus timing and controls the synchronization of the bus. Each bit transmission is divided up into a positive and a negative phase, the current supply of the bus nodes being effected in the positive phase and the data transmission being effected in the negative phase.The bus is preferably used for a hazard-detection system wherein the bus nodes comprise a micro-controller and either are constituted by special detectors with integrated bus or comprise an interface for the connection of the detectors.

Abstract: The motion detector generates a sensor signal (SS) which contains a direct current portion and an alternating current portion. The signal evaluation circuit (3) contains means for filtering out the direct current portion, an analogue-to-digital converter (4) and an amplifier for the alternating current portion of the sensor signal. The analogue-to-digital converter (4) is provided for the direct digitizing of the entire sensor signal (SS) and the means for filtering out the direct current portion are formed by a digital high-pass filter (5) connected downstream of the analogue-to-digital converter.