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Re: black gates in parallel

Robert S. I am not going to go back to completely understand your original question, but this is how I look at things. First, there is the original input surge current to charge the cap. This can in fact be 100 or more amps, IF you do NOT use a transformer and have a large enough cap. In the old days, 20+ years ago, we would insert a power resistor in front of the cap and short the resistor out with a relay, after the cap is charged. Today, we use heat sensitive 'surgistors' to limit the original charge current, and only on our best designs, do we use a shorting relay like we did in the old days. Of course, any transformer will limit the peak current, both with its winding resistance and core saturation.
Of course, once the cap is charged up, then the cap doesn't have to conduct so strongly, unless you are shorting out the cap, once it is charged up. This could happen with a flashlamp load, but I doubt that an amp would be so difficult. The exact charge current through the caps, after first charge, is difficult to predict, but it could be measured easily enough by putting in a current sensing resistor (.01) ohms or so in series with the ground leg of the cap, and measuring it with a scope. I doubt that you will see too many amps, and they will be only there for a short part of the AC cycle, so even though the I(squared) R losses could be significant, at least the cap can rest for most of the cycle.


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