For those who have never "seen" a TVSS operate, here is a screen shot of an oscilloscope trace of our standard OGR TVSS. Green trace is applied voltage, yellow
trace shows the effect of the TVSS, limiting voltage to about the peak value of a 20 VRMS voltage.
This was done with an isolated variac and a 1k resistor in series with the TVSS.
I turned up the supply voltage and let it run until the TVSS would boil water but it kept working just fine.
Just for giggles.