Tag Archives: DAR

DAR vs PI: Reading Insulation Absorption Ratios

Short answer: DAR (dielectric absorption ratio) and PI (polarization index) are both ratios taken from a timed insulation resistance test with a megohmmeter. DAR is the resistance at 60 seconds divided by the resistance at 30 seconds — a one-minute check. PI is the resistance at 10 minutes divided by the resistance at 1 minute — a ten-minute… Read More: DAR vs PI: Reading Insulation Absorption Ratios »

Dielectric Absorption Ratio (DAR) Explained: The 60-Second Insulation Diagnostic

You don’t always have 10 minutes for a full polarization index test. Sometimes you need a quick answer: is this insulation healthy or not? That’s where the dielectric absorption ratio comes in. The DAR gives you a meaningful diagnostic in just 60 seconds. It’s not as thorough as the PI, but it’s far more useful than a simple… Read More: Dielectric Absorption Ratio (DAR) Explained: The 60-Second Insulation Diagnostic »