Abstract: A safety control system includes: a first control unit arranged to control a controlled system, a second control unit arranged to detect a fault with the controlled system and arranged to transmit messages wirelessly to the first control unit, wherein the second control unit includes: a first controller and a second controller, each of the first and second controllers being arranged to detect a condition of the controlled system and output messages indicative of whether or not the condition has been detected; a transmitter arranged to transmit wirelessly to the first control unit; and a multiplexer arranged to connect each of the first and second controllers in turn to the transmitter so that messages from each of the first and second controllers can be transmitted to the first control unit.

Abstract: An active laser guarding system 1 comprises at least one screen 3 provided with at least two spaced apart conductors 7, 9 each defining a respective electrically conductive path that is electrically separate from the other. The screen 3 comprises material, at least between the two conductors 7, 9, which is arranged to carbonize when struck by a laser beam to form a further conductive path 19 which extends between, and electrically connects, the two conductors 7, 9. The system 1 further comprises a detector 15 operative to detect the further conductive path 19 so formed, the detector 15 being operative to generate a laser deactivation signal response to detecting the further conductive path 19.

Abstract: A measuring apparatus comprises a detector device for detecting a variable to be measured, and a controller operative to control the detector device and generate an output signal indicative of the magnitude of the variable being measured. The detector device comprises a housing on which are mounted two Peltier-Seebeck detectors, the detectors being arranged on the housing such that only the first Peltier-Seebeck detector is exposed, in use, to the variable to be measured. The controller is operative to generate the output signal based on the output of the first Peltier-Seebeck detector and the output of the second Peltier-Seebeck detector so as to account for the effect of the ambient heat on each Peltier-Seebeck detector.