Abstract: An arrangement for indicating correct installation of a plug-in unit (102) of a telecommunications device includes at least one distance indicator (106) located in the plug-in unit and adapted to produce an indication for correct installation of the plug-in unit in response to a situation where the distance of the distance indicator from a wall (107) of the frame of the telecommunications device is smaller than a predetermined threshold value. The distance indicator, which may be e.g. an electromechanical limit switch or capacitive distance sensor, is adapted to produce the indication for correct installation without a need for a galvanically conducted electric current between the distance indicator and the frame of the telecommunications device. There is thus no need to make any electric circuit arrangements in the frame of the telecommunications device for the indication of correct installation of a plug-in unit.

Abstract: An arrangement for indicating correct installation of a plug-in unit (102) of a telecommunications device includes at least one distance indicator (106) located in the plug-in unit and adapted to produce an indication for correct installation of the plug-in unit in response to a situation where the distance of the distance indicator from a wall (107) of the frame of the telecommunications device is smaller than a predetermined threshold value. The distance indicator, which may be e.g. an electromechanical limit switch or capacitive distance sensor, is adapted to produce the indication for correct installation without a need for a galvanically conducted electric current between the distance indicator and the frame of the telecommunications device. There is thus no need to make any electric circuit arrangements in the frame of the telecommunications device for the indication of correct installation of a plug-in unit.

Abstract: A method and an arrangement are provided for updating a first block of digital data (601) by performing a number of update operations which must either all succeed together or all fail together. The number of update operations is greater than or equal to one. A first identifier (TID) is activated (701) which is common to all those update operations that concern the first block of data and must either all succeed together or all fail together. All those update operations are performed (703) that concern the first block of data and must either all succeed together or all fail together. The updated first block of digital data is stored (707) into a logical flash memory device (1101) together with a value that associates the updated first block of data with the first identifier. The first identifier is deactivated (710).