This system consists of an insulation resistance monitoring instrument, an insulation fault location instrument, and a residual current transformer.

The insulation resistance monitoring instrument is designed for IT systems in accordance with standards GB/T18216.8 (IEC61557-8) and GB/T18216.9 (IEC61557-9). It is widely used in single-phase AC, three-phase AC, and DC systems. The AC systems can include a variety of DC-powered loads (such as rectifiers, frequency converters, and variable speed drives). The insulation resistance monitoring instrument continuously monitors the insulation resistance values of the entire IT system.

Another key function of the insulation resistance monitoring instrument is its integration with the insulation fault location instrument and residual current transformer, enabling accurate localization of insulation faults.