Abstract: An apparatus includes a voltage source, voltage measurement means and a processing means, and connects to a line to apply and monitor a voltage between the line and earth. The processing means controls the voltage source to transmit and receive communications from the line, via the voltage measurement means. The apparatus also has a first and second current measurement means. The voltage source is connectable to a wire under test to inject a predetermined test voltage on the wire. The wire extends in a first and second direction from the test location. The first current measurement means measures the leakage current from the voltage source flowing along the wire in a first direction, and the second current measurement means determines the leakage current along the wire in a second direction, and the processing means uses the current flows measured by both current measurement means to determine wire insulation properties.

Abstract: An apparatus includes a voltage source, voltage measurement means and a processing means, and connects to a line to apply and monitor a voltage between the line and earth. The processing means controls the voltage source to transmit and receive communications from the line, via the voltage measurement means. The apparatus also has a first and second current measurement means. The voltage source is connectable to a wire under test to inject a predetermined test voltage on the wire. The wire extends in a first and second direction from the test location. The first current measurement means measures the leakage current from the voltage source flowing along the wire in a first direction, and the second current measurement means determines the leakage current along the wire in a second direction, and the processing means uses the current flows measured by both current measurement means to determine wire insulation properties.