A detection device for medium voltage electric installations comprising: - a voltage sensing unit including a capacitive voltage divider sensing arrangement, said voltage sensing unit being operatively coupleable with a line conductor of an electric line and being adapted to provide first detection signals indicative of voltage levels of said line conductor; - an electronic arrangement operatively coupled with said voltage sensing unit; wherein said electronic arrangement comprises: - a first amplification stage adapted to receive and process said first detection signals and provide second detection signals indicative of voltage levels of said line conductor, wherein said first amplification stage comprises a first tuning circuit comprising one or more thermistors (Rte) of the NTC type, said first tuning circuit being adapted to tune a first amplification gain of said first amplification stage in response to environmental temperature variations, so that said first amplification stage can amplify said first detection signals and, at the same time, compensate, at least partially, temperature drift errors affecting said first detection signals due to temperature variations of said voltage sensing unit; said electronic arrangement further comprising: - a second amplification stage operatively coupled in cascade with said first amplification stage and adapted to receive and process said second detection signals and provide third detection signals indicative of voltage levels of said line conductor, wherein said second amplification stage comprises a second tuning circuit operatively coupled with a tuning terminal of said electronic arrangement, said second tuning circuit being adapted to tune a second amplification gain of said second amplification stage in response to manual interventions of an operator on said tuning terminal, wherein said second tuning circuit comprises one or more trimming resistors (R T) operatively coupled with said tuning terminal. - a voltage sensing unit including a capacitive voltage divider sensing arrangement, said voltage sensing unit being operatively coupleable with a line conductor of an electric line and being adapted to provide first detection signals indicative of voltage levels of said line conductor; - an electronic arrangement operatively coupled with said voltage sensing unit; wherein said electronic arrangement comprises: - a first amplification stage adapted to receive and process said first detection signals and provide second detection signals indicative of voltage levels of said line conductor, wherein said first amplification stage comprises a first tuning circuit comprising one or more thermistors (Rte) of the NTC type, said first tuning circuit being adapted to tune a first amplification gain of said first amplification stage in response to environmental temperature variations, so that said first amplification stage can amplify said first detection signals and, at the same time, compensate, at least partially, temperature drift errors affecting said first detection signals due to temperature variations of said voltage sensing unit; - a first amplification stage adapted to receive and process said first detection signals and provide second detection signals indicative of voltage levels of said line conductor, wherein said first amplification stage comprises a first tuning circuit comprising one or more thermistors (Rte) of the NTC type, said first tuning circuit being adapted to tune a first amplification gain of said first amplification stage in response to environmental temperature variations, so that said first amplification stage can amplify said first detection signals and, at the same time, compensate, at least partially, temperature drift errors affecting said first detection signals due to temperature variations of said voltage sensing unit; said electronic arrangement further comprising: - a second amplification stage operatively coupled in cascade with said first amplification stage and adapted to receive and process said second detection signals and provide third detection signals indicative of voltage levels of said line conductor, - a second amplification stage operatively coupled in cascade with said first amplification stage and adapted to receive and process said second detection signals and provide third detection signals indicative of voltage levels of said line conductor, wherein said second amplification stage comprises a second tuning circuit operatively coupled with a tuning terminal of said electronic arrangement, said second tuning circuit being adapted to tune a second amplification gain of said second amplification stage in response to manual interventions of an operator on said tuning terminal, wherein said second tuning circuit comprises one or more trimming resistors (R T) operatively coupled with said tuning terminal.