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picbits Thank you. I was considering a few options to hook to a momentary switch to bleed it. An LED with a resistor, a 24v fan or just using a small Xmas light bulb which doesn't require me to spend any $ or have to order something online since Radio Shack is non-existent. I have a bleed resistor but adding the bulb would allow me to know/see if they are bled.
You never mentioned the capacitance. If it has a low capacitance then the light duration will be too small for it to warm up.
The Christmas tree lights I used 10 years ago (all LEDs now) were 2.5V I think with 48 of them in series to make them light from 120V.
What will happen to a 2.5V light bulb with 24V on it?
It is bleeding a 100,000uf 50V cap in a mig welder that I am converting from AC to DCEN. I can use a small bulb. It will be inside the welder cabinet. Actually, I guess the easiest thing to do is just use the 100W 15ohm bleeder I have and put a meter across it once and see how long it takes to bleed it down and just make sure I hold the switch down that long whenever I'm done. I'm using the switch because I don't want the caps to discharge each time I let go of the trigger but want to bleed it when I'm done. The light just provides visual confirmation. I'm not an EE so this is related to this post. https://www.electro-tech-online.com/threads/momentary-switch-and-led.121208/page-2#post-1346083
The resistivity of tungsten varies with temperature, roughly 0.4% per degree K, so the resistance of an incandescent lamp at its operating temperature of roughly 2800K is much higher than its cold resistance.
I made some measurements of I vs. V on a few incandescent light bulbs and plotted their resistance versus voltage. For a 100 watt, 120 volt bulb, this was the result:
I've just measured a 100W 240V bulb resistance and yes, it is pretty low at 40R (took me ages to find an "old school" bulb) so with a 100W 110V bulb a 10R would be perfectly feasible (I stand corrected).
Some people drive old cars, with carburetters, kettering ignition and no catalytic converter, for fun
Some people ride horses for fun.
Some people walk and run for fun.
Some people play with old radios with vacuum tubes and transmit SSB and CW (morse), for fun.
I must say that the young, aspiring engineers that I know all look on EE-related forums for answers/explanations to their problems (most don't even have accounts). The funny thing is, they all seem to know the name "audioguru" and his Uncle Scrooge avatar.