An electro impedance measuring belt for placing electrodes around the thorax of a patient comprises an array of a plurality of spaced apart electrodes, and a support structure, on which the electrodes are arranged. The support structure with the electrode array comprises two angulated legs on which the electrodes are lined up, the two legs spread out from an apex at an angle, such that, when the belt is put around the thorax of a patient, the array of electrodes extends from the back of the patient, where the apex of fee angulated legs is to be located, essentially parallel to the ribs to the lower part of the breastbone of the patient.