Abstract: Disclosed is a sensor shield for use in a multi-shelf merchandise display unit including a plurality of sensors mounted on a wall of the unit and opposite a source of illumination, in which each sensor corresponds to a single shelf and in which the shelves are at least semi-porous to the illumination. The shield comprises i) a plate having a length that is sufficient substantially to reduce or prevent incident illumination from the shelf above reaching the sensor; and ii) means to attach the plate to casing of or around the sensor or the wall of the unit. The plate is opaque to the illumination detected by the sensor. Also disclosed is a method to reduce the interference of light in a multi-shelf merchandise display unit from shelves above a shelf on which stock levels are being measured and a method for monitoring stock levels in a retail display cabinet by measuring light entering the retail display cabinet.

Abstract: Disclosed is a method to enable a retail display or vending unit to switch to or from an energy saving mode. The method comprises listening for a radio frequency emitted by a mobile telephone and switching the unit from an energy saving mode when a radio frequency is detected and switching the unit to an energy saving mode when no radio frequency is detected. Also described is a retail display or vending unit comprising means to detect a radio frequency emitted from a mobile telephone and means to enable automatic switching off of components and/or processes and systems within the unit when low or no radio frequency is detected and to switch on components and/or processes and systems within the unit when radio frequency is detected.

Abstract: Described is a method for maintaining a retail display or vending unit. The method includes obtaining and storing data from sensors located in or on the unit in a control system including data communication means, wherein the data is sent to and accessed by remote telecommunication means via the data communication means, and wherein operation of the unit is changed based on the data.

Abstract: Disclosed is a sensor shield for use in a multi-shelf merchandise display unit including a plurality of sensors mounted on a wall of the unit and opposite a source of illumination, in which each sensor corresponds to a single shelf and in which the shelves are at least semi-porous to the illumination. The shield comprises i) a plate having a length that is sufficient substantially to reduce or prevent incident illumination from the shelf above reaching the sensor; and ii) means to attach the plate to casing of or around the sensor or the wall of the unit. The plate is opaque to the illumination detected by the sensor. Also disclosed is a method to reduce the interference of light in a multi-shelf merchandise display unit from shelves above a shelf on which stock levels are being measured and a method for monitoring stock levels in a retail display cabinet by measuring light entering the retail display cabinet.