A method and system for multi-electrode monitoring of an internal electrical impedance of a biological object, using placing two arrays of electrodes on opposite sides of the biological object, wherein each of said two arrays comprise at least two spaced apart electrodes performing session of measurements comprising imposing an alternating electrical current between pairs of said electrodes and obtaining voltage signals representative of a voltage drop thereon calculating values of skin-electrode resistance for all said electrodes comparing said calculated values of skin-electrode resistance therebetween, wherein result of the comparison exceeding a predetermined threshold value being representative of a potential failure in at least one of said electrodes.
