I was just wondering. When you say 400v it is because you cant get anything at 230v right? it goes from 200v to 400v atleast when we talk diodes. (and I do use a 1kv diode
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The peak voltage of a 230VAC sine wave is 325V.
The capacitor will charge to the peak voltage, minus the tiny rectifier loss, not the RMS voltage.
If the mains voltage is 10% high, the RMS voltage will be 253V and the peak will be 358V, add a reasonable safety margin and you get 400V.
If the capacitor is charged to 357V, and the mains voltage reverses, the peak reverse voltage across the diode will be 357V + 358V = 715V, add a reasinable safety margin and you need a 750V rectifier, the 1V difference is due to the rectifier losses and rounding errors in my calculation.
Hmm all these high voltage komponents. For making a spark I could just use the automotive ignition coil add 12v and get a suitable 312v out to make the spark? And then I dont need these high voltage komponents? Thats only for making big sparks.
312v should be good enough, and I will be able to use a small 16v capacitor and normal resistor and 4001 diode right?
312V is no where near high enough to make a spark, as a general rule you need 1.1kV per mm.
312V is actually classed as low voltage, high voltage is over 1kV.
An ignition coil produces a much higher voltage than 1kV, normally 5kV minimum, often higher.