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In a text it mentions about a power supply that the filter cap will act as a short at initial turn-on. Below I showed these points as A and B:

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In this case, the diode will have a surge current Is. And the text says this Is current should be limited by a resistor between the transformer and each diode.

But in practice isn't transform's winding enough to limit this current? What is the typical value for this resistor lets say for a 24V power supply? Im asking because I dont see any such series resistors in examples. Im wondering is it fine to neglect it.

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    \$\begingroup\$ This is precisely why rectifier diodes usually have a "single-cycle surge" rating that is much higher than their continuous current rating. \$\endgroup\$
    – Dave Tweed
    Commented Oct 19, 2017 at 14:51

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Stating that this current should be limited by resistors indeed ignores the fact that the current is already limited by the transformer winding's series resistance, the diode's series resistance and the capacitor's ESR. Often there is a fuse present as well and don't forget the resistance of the wires.

Also, the current might not need to be limited if it is within limits already.

Also, what would break first if the current is too high? My guess is that the diodes would break first. Most rectifier diodes can handle very large currents for a short time. Like the 1 Ampere 1N400x series diodes can handle peak currents of 30 Amps.

A resistor value for a 24 V supply cannot be given as it depends a lot on the maximum current which that supply is designed for and what other components are used.

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