Permanent
Permanent HFCT sensors are installed inside the HV cable box (of the switchgear, transformer or rotating machine) to enable OLPD testing and/or monitoring of in‑service MV/HV cable circuits without the need for an outage. We also supply Ex/ATEX versions of this permanent HFCT sensor for use in hazardous gas zones in the oil & gas industry.
Portable
Portable, split-core HFCT sensors are used when the earth connections of the HV cable are outside of the cable box.
The sensors can also be installed inside the de‑energised and isolated cable boxes of switchgear, transformers or rotating machines for temporary testing or monitoring if the earth connections are not available outside the cable box (requires an outage).
