Tony,
It seems unlikely to me that your AC mains power would be THAT distorted
(non-sinusoidal) that it would significantly affect the thyristor trigger
point. I'm not a power engineer, but I think it would cause significant
problems elsewhere (to many other devices) if your utility company was
sending you severely distorted waves. But I don't know what the standards
are.
Is there "any possibility"? Well, I suppose so, however unlikely.
If you don't get enough heat when cranked up, then this is not the cause.
RMS voltage is RMS voltage.
Changing the thyristor trigger point has been used for decades in light
dimmers. Do you have any light dimmers and do they still work?
FYI, my AC mains voltage here (USA) has been running a tad below 100V RMS
many days during the last month. Nominal is 115-125V. That's about 17%
below normal voltage, at least 30% low on power with a constant resistive
load. LED and CFL lighting seems to mostly ignore it, as does good
electronic gear, so you might not notice that you are having a brownout
unless you still have incandescent lamps.
Andy
