Polarity Index Calculator for Insulation Resistance

Polarity Index Calculator for Insulation Resistance calculator can be used to determine the quality of insulation in electrical systems by comparing the resistance values measured between different terminals. This helps in identifying issues like moisture ingress, contamination, or aging of insulation materials.

Input Parameters

Calculation Results

Calculation Formula

Polarity Index (PI) = (Reading 1 + Reading 2 + Reading 3) / 3

Where:
Reading 1, Reading 2, and Reading 3 are the insulation resistance measurements in megohms (MΩ)

Polarity Index Calculator for Insulation Resistance Calculator Usage Guide

Learn how to use the Polarity Index Calculator for Insulation Resistance calculator and its working principles

How to Use the Calculator

  1. Enter the three insulation resistance readings in megohms (MΩ) taken between different terminals of the equipment.
  2. Click the "Calculate" button to compute the Polarity Index (PI).
  3. The calculator will display the Polarity Index and provide an interpretation based on the calculated value.

Understanding the Polarity Index

The Polarity Index (PI) is a measure of the quality of insulation in electrical systems. It is calculated by averaging the insulation resistance readings taken between different terminals. A higher PI value indicates better insulation quality, while a lower value suggests potential issues.

Interpretation Guidelines

  • PI ≥ 2: Good insulation condition. No immediate concern.
  • 1 ≤ PI < 2: Moderate insulation condition. Monitor periodically.
  • PI < 1: Poor insulation condition. Immediate action recommended.

Principle of Operation

The calculator uses the formula: PI = (Reading 1 + Reading 2 + Reading 3) / 3. This formula provides a simple average of the three resistance readings, helping to identify any significant deviations that might indicate insulation problems.