Method for contact-free detection of granular material within an agricultural distribution machine, comprising the steps of: - conveying the granular material by means of pressure difference and/or gravity through an electronic appliance which has at least one sensor device; - detecting the granular material by means of the at least one sensor device; the sensor device being designed to generate a sensor signal depending on the detected material and on the basis of a sensitivity which can be adjusted for the sensor device; - determining an actual frequency at which the granular material passes through the electronic appliance, in particular the sensor device, on the basis of the sensor signal, - comparing the determined actual frequency with a retrievable and/or predeterminable target frequency at which the granular material is conveyed through the electronic appliance; - determining a deviation between the actual frequency and the target frequency; - automatically or automatedly adjusting the sensor signal and/or the sensitivity until a predeterminable acceptance range for the deviation is reached; the sensor signal and/or the sensitivity being adjusted by a control and/or regulation system assigned to the electronic appliance and/or to the distribution machine; characterized by the step of: - providing an adjustable electrical power supply for the at least one sensor device, a brightness of a light source assigned to the sensor device, for detecting the granular material, being adjustable depending on the power supply; the electrical power supply automatically increasing or decreasing until the acceptance range for the deviation is reached. - conveying the granular material by means of pressure difference and/or gravity through an electronic appliance which has at least one sensor device; - detecting the granular material by means of the at least one sensor device; the sensor device being designed to generate a sensor signal depending on the detected material and on the basis of a sensitivity which can be adjusted for the sensor device; - determining an actual frequency at which the granular material passes through the electronic appliance, in particular the sensor device, on the basis of the sensor signal, - comparing the determined actual frequency with a retrievable and/or predeterminable target frequency at which the granular material is conveyed through the electronic appliance; - determining a deviation between the actual frequency and the target frequency; - automatically or automatedly adjusting the sensor signal and/or the sensitivity until a predeterminable acceptance range for the deviation is reached; the sensor signal and/or the sensitivity being adjusted by a control and/or regulation system assigned to the electronic appliance and/or to the distribution machine; characterized by the step of: - providing an adjustable electrical power supply for the at least one sensor device, a brightness of a light source assigned to the sensor device, for detecting the granular material, being adjustable depending on the power supply; the electrical power supply automatically increasing or decreasing until the acceptance range for the deviation is reached. - providing an adjustable electrical power supply for the at least one sensor device, a brightness of a light source assigned to the sensor device, for detecting the granular material, being adjustable depending on the power supply; the electrical power supply automatically increasing or decreasing until the acceptance range for the deviation is reached.