The current adjustment by magnetic shunt does not change the open circuit voltage, while the triac controller decreases the primary voltage, and therefore also that of the secondary.
When we replace HV coil with something desired for high current, not too much space left for oryginal MOT magnetic shunts, so probably I'll try to make this tricky additinal magnetic circuit on top of this thing
Anyway, during testing my new upgraded (spot) welder software, I forgot change current limit set for testing in mains Hall current sensor configuration and left it at.. 0.5A RMS level
and I've almost rewritten turn on/off button software averaging and contoll, since... software was good for button event processing and starting transformer SCR's, but of course inrush currents were much bigger than 0.5A rms (100ms), so when I had no idea howto write better MPU pin interface, after a few hours of
and debuging, I've found this bloody definition which puzzled me for so long time
#define FUSE_CURSEN_LIMIT (0.5)
Beauty of software development - one line of code can ruin your day or let magic to happen other time
Yep, using phase controll to limit output current can degrade voltage, too, but in my case It shouldn't be a problem- I'll have HV high frequency pulses in series with welder transformer.
However, phase shift control can be very usefull for demagnetization of transformer core and developing such soft start code for my ATTiny85 MPU right now