Abstract: A device for the automatic control of joints 5 in electrical high voltage lines is disclosed. It comprises a first support 1, a first wheel 2, for lying on a line 4, a driver for driving the first wheel 2, at least one second wheel 3 for lying on the line 4, a measurement unit 11, in contact with a device for measurement of physical data at the joint. The device includes at least one pointed element 7,8,9 for electrical contact with the line 4. The device is especially characterized in that at least one wheel 2,3 is provided electrically connected to the measurement unit.