Insulation Resistance Profile (IRP) and its use for assessing insulation systems

After decades of research in insulation systems, little has been published in the area of analyzing the graph of resistance versus time. Plotting the Insulation Resistance versus Time, gives a graph which may be referred to as an “Insulation Resistance Profile” or IRP. In addition to the standard Insulation Resistance (IR) value and the Polarization Index (PI) value, an Insulation Resistance Profile (IRP) may provide useful information as to the condition of the insulation system. The condition of the insulation system will typically yield one of four profiles: Normal, Moisture, Contamination, or Embrittlement. Additionally, these profiles may yield useful information when the insulation resistance exceeds 5000 Megohm that may otherwise have been overlooked.