A disconnector comprising: a switch, the switch comprising: a first, fixed, contact terminal of a first conductor, a second, fixed, contact terminal of a second conductor, and a moveable bridge contact; an actuating mechanism configured to open and close the switch by actuation of the moveable bridge contact, wherein the actuating mechanism is configured to move the bridge contact in a direction from a first position to a second position, wherein in the first position the switch is closed and the bridge contact is in electrical contact with the first and second contact terminals to define a current conduction path, and wherein in the second position the switch is open and the bridge contact is electrically separate from the first and second contact terminals; a detection coil, the detection coil configured to output a signal indicative of a current through the respective contact terminal; a communication module communicatively coupled to the detection coil and configured to receive the signal indicative of a current through the respective contact terminal and provide an output signal in dependence on the received signal; and characterised in that said detection coil is disposed around the first contact terminal or the second contact terminal of the switch; the circuit breaker further comprising a housing comprising a front portion which is accessible to a user in normal use, wherein the switch is disposed within the housing and the communication module is external to the housing, and wherein: the communication module is coupled to the front portion of the housing, and/or the detection coil is accessible through the front of the housing. a switch, the switch comprising: a first, fixed, contact terminal of a first conductor, a second, fixed, contact terminal of a second conductor, and a moveable bridge contact; a first, fixed, contact terminal of a first conductor, a second, fixed, contact terminal of a second conductor, and a moveable bridge contact; an actuating mechanism configured to open and close the switch by actuation of the moveable bridge contact, wherein the actuating mechanism is configured to move the bridge contact in a direction from a first position to a second position, wherein in the first position the switch is closed and the bridge contact is in electrical contact with the first and second contact terminals to define a current conduction path, and wherein in the second position the switch is open and the bridge contact is electrically separate from the first and second contact terminals; a detection coil, the detection coil configured to output a signal indicative of a current through the respective contact terminal; a communication module communicatively coupled to the detection coil and configured to receive the signal indicative of a current through the respective contact terminal and provide an output signal in dependence on the received signal; and characterised in that said detection coil is disposed around the first contact terminal or the second contact terminal of the switch; the circuit breaker further comprising a housing comprising a front portion which is accessible to a user in normal use, wherein the switch is disposed within the housing and the communication module is external to the housing, and wherein: the communication module is coupled to the front portion of the housing, and/or the detection coil is accessible through the front of the housing. the communication module is coupled to the front portion of the housing, and/or the detection coil is accessible through the front of the housing.