AC Isolation Monitor

[dtryon]

Hey Folks,
I have tried to look but I can't find anything like I'm looking for. What I need is a circuit or kit or PC board design that will monitor AC line isolation. I need this to operate on a continuous basis. I want to monitor test equipment and or equipment under test so it remains isolated while being worked on. I would think someone has already designed something to do this function. I don't want to reinvent the wheel, lol. Can anyone help me with this problem?

Thanks,
Dennis