Thank you Malcolm; yes, electrosurgical units were always one of my "specialist subjects"!
The equipment under consideration (TD-830) has "leakage limiting" circuitry ... but the question must be:- how long does it take to kick in (respond)? Not fast enough to out-wit Howard's nice tester, I'm guessing.
That's part of the problem with a lot of modern biomed test equipment ... it's smarter than (out-performs) the kit it's meant to be testing (and often the testing Standard(s) as well).
In Happy Days of Yore we had to make do with whatever we had to hand - sometimes just a piece of fresh liver from the cookhouse!
Meanwhile, and as we're talking about ESU testing ... what about the "accessories"
? Often (usually?) overlooked, but still potentially dangerous.
PS: yes; "steady value during ... testing" - always let things settle to steady state (unless, of course you're deliberately trying to capture a "spurious signal").