Continuous Remote OLPD Monitoring of HV Rotating Machines

This technology, which has three patents granted against it, has been designed specifically for the on-line PD monitoring of Rotatng Machines, including Ex/ATEX HV motors and generators located in hazardous gas zones.

With this solution, which incorporates HVPD Kronos® Monitors and advanced software algorithms, it is possible to carry out remote OLPD monitoring of complete HV circuits. This technology is not restricted to the Ex/ATEX motors and can monitor the insulation condition of cables, switchgear and transformers, achieving complete network monitoring.

This technique makes it possible to differentiate between all three types of PD that could originate from an HV motor feed circuit, including switchgear PD, cable PD and the different types of HV stator winding PD using a combination of wideband, HFCT and TEV sensors installed at the switchgear cable box.
In 2014, this solution also earned HVPD a Queen's Award for Enterprise in the Innovation catergory.


  • The HVPD Kronos® Monitor's synchronous measurement allows for differentiation between end winding (phase-to-phase) and slot section (phase-to-earth) PD.
  • Allows for monitoring of four complete HV motor feeders with OLPD sensors installed at the central switchboard.
  • Provides a warning of HV insulation deterioration before it causes costly equipment failure and unplanned outages.
  • Compares and benchmarks the motor's PD activity to the HVPD OLPD Measurements Database©.
  • Network-enabled through SCADA integration protocols, such as DNP3, Modbus, OPC (other protocols can be used on request).
  • Provides comprehensive complete MV/HV network monitoring.
  • Dedicated support with HVPD Kronos® Care service contract.

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