A sensor for detecting voltage on a transmission line having an insulator and a conductor, the sensor comprising: a housing configured to mechanically encircle, and extend lengthwise along, a portion of the transmission line; at least one probe conductive plate coupled to the housing and configured to encircle at least one first part of the portion of the transmission line encircled by the housing, the at least one probe conductive plate further configured to form at least one probe capacitor with the at least one first part of the portion of the transmission line; a measurement conductive plate coupled to the housing and configured to encircle a second part of the portion of the transmission line encircled by the housing, the measurement conductive plate further configured to form a measurement capacitor (Cmeasure) with the second part of the portion of the transmission line, the measurement capacitor having a known geometric and resulting electrical relationship with the at least one probe capacitor; a capacitance acquisition system coupled to a first probe conductive plate of the at least one probe capacitor, and coupled to the measurement conductive plate, the capacitance acquisition system being galvanically isolated from the conductor; and a voltage measurement system coupled to the measurement capacitor and configured to communicate with the capacitance acquisition system, wherein the capacitance acquisition system is configured to determine a first value related to capacitance of the at least one probe capacitor, and based on the first value, determine a capacitance value of the measurement capacitor; and wherein the voltage measurement system is configured to receive a signal providing the capacitance value of the measurement capacitor from the capacitance acquisition system and calculate a second value related to a voltage level of the transmission line. a housing configured to mechanically encircle, and extend lengthwise along, a portion of the transmission line; at least one probe conductive plate coupled to the housing and configured to encircle at least one first part of the portion of the transmission line encircled by the housing, the at least one probe conductive plate further configured to form at least one probe capacitor with the at least one first part of the portion of the transmission line; a measurement conductive plate coupled to the housing and configured to encircle a second part of the portion of the transmission line encircled by the housing, the measurement conductive plate further configured to form a measurement capacitor (Cmeasure) with the second part of the portion of the transmission line, the measurement capacitor having a known geometric and resulting electrical relationship with the at least one probe capacitor; a capacitance acquisition system coupled to a first probe conductive plate of the at least one probe capacitor, and coupled to the measurement conductive plate, the capacitance acquisition system being galvanically isolated from the conductor; and a voltage measurement system coupled to the measurement capacitor and configured to communicate with the capacitance acquisition system, wherein the capacitance acquisition system is configured to determine a first value related to capacitance of the at least one probe capacitor, and based on the first value, determine a capacitance value of the measurement capacitor; and wherein the voltage measurement system is configured to receive a signal providing the capacitance value of the measurement capacitor from the capacitance acquisition system and calculate a second value related to a voltage level of the transmission line. wherein the capacitance acquisition system is configured to determine a first value related to capacitance of the at least one probe capacitor, and based on the first value, determine a capacitance value of the measurement capacitor; and wherein the voltage measurement system is configured to receive a signal providing the capacitance value of the measurement capacitor from the capacitance acquisition system and calculate a second value related to a voltage level of the transmission line.