Attention Electrical Engineers and Physicists! Light bulb as current regulator?
If I understand correctly, an incandescent light bulb conducts with negligible resistance until it reaches a critical point at which point it resists any more… More what? More current? More voltage?
The situation is this: I have made an AC arc welder out of microwave oven transformers but I have no control system. This welder works great for about an inch of weld then starts blowing the breaker until it cools off. (You’d think it would be the opposite with resistance increasing and current decreasing as the coils warm up, but it’s not… Why?)
So what if I put three 500 watt light bulbs in parallel with each other but in series with the welder? Could this work as a 1500 watt current regulator?
And if I did this, where should I put the bulbs? Should they be in series with the 110v side of the transformers or on the ~40v side of the transformer? I figure they should be on the 110v side but then they’d be on all the time, heating up the primary windings, right? Or should they be in series with the secondary windings? This way they’d only be in when I’m actually welding but they’d have to conduct a lot more amperage.
What would jyou do?