Sensored insulation plug (1, 2, 3) for being inserted into a rear cavity of a medium voltage or high-voltage separable connector in a power distribution network of a national grid, and operable to insulate a connection element of the separable connector on an elevated voltage and to sense the elevated voltage, the sensored insulation plug comprising a) a plug body formed by a solidified insulating material, b) an externally accessible detection contact, c) a primary capacitor, operable as a high-voltage capacitor in a sensing voltage divider for sensing the elevated voltage, the primary capacitor having i) a high-voltage electrode for direct electrical connection to the elevated voltage; ii) a sensing electrode of a tubular shape, embedded in the plug body; and iii) a dielectric formed by a first portion of the insulating material arranged between the sensing electrode and the high-voltage electrode, and d) a testpoint capacitor, operable as a high-voltage capacitor in a detection voltage divider for detecting the elevated voltage and comprising i) the high-voltage electrode; ii) a testpoint electrode, embedded in the plug body and electrically connected to the detection contact; and iii) a dielectric formed by a second portion of the insulating material arranged between the testpoint electrode and the high-voltage electrode, wherein the sensored insulation plug further comprises e) a signal wire electrically connected to the sensing electrode, the signal wire having an excess wire portion arranged outside the plug body, and f) a wire holder, externally attached to the plug body or to the detection contact, for holding the excess wire portion in fixed spatial relation to the plug body. a) a plug body formed by a solidified insulating material, b) an externally accessible detection contact, c) a primary capacitor, operable as a high-voltage capacitor in a sensing voltage divider for sensing the elevated voltage, the primary capacitor having i) a high-voltage electrode for direct electrical connection to the elevated voltage; ii) a sensing electrode of a tubular shape, embedded in the plug body; and iii) a dielectric formed by a first portion of the insulating material arranged between the sensing electrode and the high-voltage electrode, and i) a high-voltage electrode for direct electrical connection to the elevated voltage; ii) a sensing electrode of a tubular shape, embedded in the plug body; and iii) a dielectric formed by a first portion of the insulating material arranged between the sensing electrode and the high-voltage electrode, and d) a testpoint capacitor, operable as a high-voltage capacitor in a detection voltage divider for detecting the elevated voltage and comprising i) the high-voltage electrode; ii) a testpoint electrode, embedded in the plug body and electrically connected to the detection contact; and iii) a dielectric formed by a second portion of the insulating material arranged between the testpoint electrode and the high-voltage electrode, wherein the sensored insulation plug further comprises i) the high-voltage electrode; ii) a testpoint electrode, embedded in the plug body and electrically connected to the detection contact; and iii) a dielectric formed by a second portion of the insulating material arranged between the testpoint electrode and the high-voltage electrode, wherein the sensored insulation plug further comprises e) a signal wire electrically connected to the sensing electrode, the signal wire having an excess wire portion arranged outside the plug body, and f) a wire holder, externally attached to the plug body or to the detection contact, for holding the excess wire portion in fixed spatial relation to the plug body.