The invention relates to a method for triggering a transmission of sensor data from a wireless device comprising at least one accelerometer. The wireless device is arranged to an automatic door. The method comprises: receiving from the wireless device data processed from the sensor data; analyzing the received data processed from the sensor data; and generating a control signal to the wireless device in response to a detection of a predefined event, wherein the control signal comprises at least a request to the wireless device to trigger the transmission of sensor data. The invention also relates to a network node and a system performing at least partly the method.