Test Equipment for Galvanic IR vs Dielectric (Hi-Pot) Withstand Testing Requirements

What is the difference between the test equipment required to conduct IR test and Dielectric (Hi-Pot)

In reading a large OEM sepcification, Two tests we are required to complete are Dielectric withstand

1500VACrms @ 50Hz for 1 minute for terminals >115VAC -or-
500VDC for 1 minute for terminals

I thought galvanic insulation resistance is measured in Ohms because it's supposed to estimate what leakage current to expect during normal operation due to your insulator not being perfect. I've never had any problems where I personally had to worry about the spec though.

Conversely, I thought the dielectric withstand is more for estimating how much voltage can be applied before insulator breakdown occurs (not normal operation) to make sure no arching conduction will occur in a given application. I've had to be conscience of this in high voltage transformers before to make sure there is a reasonable safety margin. Maybe they force breakdown and measure the Amps and that's why its a current measurement?

I don't know anything about the test and measure procedures themselves, and to be honest my understanding of the specs could be off base too.

Here are some resources that you might find helpful.

"HiPot Testing FAQ":http://cirris.com/testing/guidelines/hipot_testing.html

Ah, useful, thanks for running down that information Cody. If that's accurate than in my response I was confusing dielectric withstand with dielectric breakdown testing (I didn't realize there was a difference).

If I understand what the page is saying about dielectric withstand and insulation resistance testing then the answer to Jim's question is that there isn't a difference between those test procedures. As long as you are allowed to use the same voltage and duration for both tests it seems to imply you just use Ohm's law to calculate out the insulation resistance.