The CHAR system by AMS Corp. (USA) assess the condition and functional integrity of cables through non-destructive electrical testing. The characteristic of the instrument is that it can evaluate cable problems that cannot be detected by conventional testing or lack sensitivity, including insulation local aging and mechanical fault localization and severity assessment (FDR), cable shielding layer damage localization (RTDR), etc.

The FDR broadband impedance testing function uses a VNA module (dynamic range up to 130dB), which allows for defect (fault) localization, status diagnosis, and aging trend analysis testing of cables from the control cabinet without the need to remove terminal loads. The CHAR system can not only be used for testing power cables, but also for control and communication cables without armor shielding. It is widely used in fields such as power grids, nuclear power, and railways.