One thing that surprised me was that with my fluke 77 meter I would typically measure 125vac from the wall. Tonight the KAW shows 118vac. I double checked it from my meter and it shows 120vac (L-N).
My ST120 is on a variac and I wanted to confirm the output of it so I initially checked from L-Ground and got 146vac! I kinda freaked and turned it down to 117vac. Then I checked from L-N and only measured 47vac. Then I looked at the amp and noticed the filaments were barely glowing so I turned it back up to 117vac (L-N). I went back to measure L- ground and now show 155vac! Fascinating.
I also plugged one of those polarity checkers into the wall and my assortment of filtered power strips and they all checked out correctly wired however when I plugged it into the variac I just get the red led lit. I guess this is just how a variac works.