What value of power would you use for the resistors that break up the circuit in parallel with the coil?
If you use 270V, and the value is 460 ohm each, you get the following:
Simulated with a 80mOhm resistance in the 250uH coil, and 80mOhm resistance in the secondary coil (higher because of all the solder joints despite being much shorter), and 5 ohms of series resistance with the 7.5uF capacitor. The parameters of the primary capacitor (2uF) can be ignored I think.
0.01Ohm Load - Short Circuit - 60mA, 470 Ohm 4x - so approx 2k parallel.
Peak Power - 1.6kA for the load, which is approximatly 7 watts, across 4 resistors, so 1.8 watts per resistor, meaning you should use 3watt resistors. This means something shorted out real good. Possible even?
3 ohm load - 80Amps flowing through coil, 3.4mA going through the resistors, 18mW per resistor, so 1/4 watts is more then acceptable
7.5 ohm load - 35 amps flowing through coil.. 1/4 watt parallel resistor more then acceptable. The 2.65mm wire inside can handle it, if hooked into a 40 amp 2 phase outlet. Would need a special connector on it though.
Now, I assume this beast should be fused.... so slow blow fuses? I don't know what the dynamic resistance of these guys is.
As you can see the theoretical spread is pretty large. What would be a good practical value of wattage to use? What is the expected peak current from a reasonable outlet? How should a resistor be rated (I don't really see transient power specs on resistors).
Do I need to go with 3Watt resistors to account for the possibility of the load shoring out? Or is this completely insane? How do you derate average resistance for a pulse that lasts in the microseconds? I assume its pretty nonlinear with respect to the gauge of wire used to manufacture the resistor.
What kinda average current that the resistor cares about will a shorted outlet put out before the circuit breaker/fuse kicks in? I think the resistors can be damaged by hot spots.. but the time scales of these overloads ellude me, and the overload duration of the resistors cannot be easily found.
Getting a kiloamp from a 20amp home outlet seems kinda unlikely, no matter how short the pulse is, but then again its a spark gap so .
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My hunch says I should just put like 0.75 watts of dissipation per resistor to tolerate stuff.