Insulation Resistance and Polarization Index Test

Inspection template for recording Megger insulation resistance and polarization index (PI) test results on motors and cables, including one-minute and ten-minute readings, temperature correction, and acceptance documentation aligned to IEEE 43 practices.

Inspection Details

• Asset type
  Select the equipment being tested.
• Asset identification
  Record equipment tag number, feeder ID, or cable circuit identifier.
• Location
  Record the physical location or room where the test was performed.
• Test date and time
  Record when the insulation resistance test was performed.
• Test purpose
  Select the reason for the test.

Safety and Test Preconditions

• Lockout-tagout applied and verified
  Confirm the equipment is isolated, de-energized, and locked out/tagged out before testing.
• Absence of voltage verified
  Confirm absence of voltage using an approved meter before connecting the Megger.
• Test leads and meter condition acceptable
  Inspect the insulation tester, leads, clips, and probes for damage, contamination, or loose connections.
• Work area controlled and barricaded
  Confirm the test area is controlled so unauthorized personnel cannot contact exposed conductors.
• PPE appropriate for electrical testing
  Verify required PPE is worn per site electrical safety procedure and task hazard assessment.

Environmental and Test Conditions

• Ambient temperature
  Record ambient air temperature at the test location.
• Winding or conductor temperature
  Record the measured or estimated insulation temperature used for correction.
• Relative humidity
  Record humidity if available, as it may affect interpretation of results.
• Insulation system condition
  Select the observed condition of the insulation before testing.
• Temperature correction factor applied
  Enter the factor used to correct insulation resistance to the reference temperature.

Insulation Resistance Test Results

• Test voltage
  Record the DC test voltage applied by the insulation resistance tester.
• One-minute insulation resistance
  Record the insulation resistance reading at one minute.
• Ten-minute insulation resistance
  Record the insulation resistance reading at ten minutes.
• Polarization index
  Calculate PI as ten-minute reading divided by one-minute reading.
• Temperature-corrected insulation resistance
  Record the corrected insulation resistance value at the reference temperature.

Acceptance, Deficiencies, and Closeout

• Results meet acceptance criteria
  Confirm the readings meet the project, OEM, or IEEE 43-based acceptance criteria used for this asset.
• Deficiencies noted
  Select any deficiencies observed during the test or review.
• Corrective action / follow-up
  Describe corrective action taken or recommended follow-up, including retest, drying, cleaning, or repair.
• Inspector signature
  Inspector sign-off confirming the test record is complete and accurate.