Iris Power Corona Probe (PPM-97)

Offline Partial Discharge Testing

The corona probe locates partial discharge sites in stator winding insulation

Hydro Generator
Turbine Generator
Works with These Assets


This an off-line instrument to accurately pinpoint the source of partial discharge (PD) in a particular slot in generators and motors. Complete kit comes with PPM-97 peak pulse meter, ferrite probe, ground strap and handy carrying/storage case. The Corona Probe (originally known as the TVA probe) is used to locate partial discharge in each slot with the winding energized phase by phase. It supplements on-line partial discharge monitoring. The PPM-97 probe is generally used on motors and generators with rated voltage greater than 6 KV.

  • Continuous wave sensitivity: 0.9 V RMS
  • Batteries: 9 V
  • Light-weight and portable
  • Recommended in IEEE® Standard 1434™

Group Created with Sketch. Applications

  • Offline PD test for locating activity in the winding
  • Precisely locates PD to a particular stator slot and position
  • Locates partial discharge with the winding energized phase by phase
  • Can check the quality of bonding between groundwall insulation layers in the slot sections of new resin-rich and individually VPI’d coils/bars, and
    the adequacy of slot resin fill in global VPI windings