I am using a rectifier, and 4500uF capacitor to reduce the ripple. After connecting to the power source (60Hz, 120V), I was able to turn on the fan. The issue occurs when I turn the switch on to power the other load. Below is the schematic. After turning the switch on to power the processor, the fan would start slowing down. I have noticed that the ripple does increase after adding another load. I have tried adding multiple capacitor on the output of the rectifier, and it would only increase the delay in fan slowing down. I am positive that the rectifier can output more than 20Amps. Both the load added takes in less that 11Amps.

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Is there anything I can add to this circuit to help reduce the effect on the fan when the switch has been turned on to power the processor?

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    \$\begingroup\$ Is the 160V to 24V converter voltage regulated? If not, it sounds like you have increased voltage drop in the rectifiers and/or wiring with increasing load, and that is lowering the voltage to the fan. \$\endgroup\$ – crj11 Sep 21 '20 at 2:50
  • \$\begingroup\$ It's perfectly normal and expected that ripple increases under a heavier load. In fact, a proper design will plan on that fact and arrange for the capacitor sizing (in a simple design like this one) such that the ripple is at or below some desired maximum. But you must also realize that the drop across the diodes also increases with increased current. And finally that the diodes only conduct for a short period, so their peak current is usually very much more than the average current needed. \$\endgroup\$ – jonk Sep 21 '20 at 2:51
  • \$\begingroup\$ @crj11, once the switch is turned on to power the processor, the ripple increases but the issue is that no matter how many capacitor I add, it will only delay the unavoidable; the fan will slow down later. 160V TO 24V is regulated. The minimum voltage that converter takes is 100V. The ripple goes below 100V. \$\endgroup\$ – Sam Shurp Sep 21 '20 at 2:58
  • \$\begingroup\$ Check the fan voltage. Is it a steady 24v? or does it decrease when you power on the second load? If that's not it, then maybe the ripple is not being rejected by the regulator, in that case try a different reg. \$\endgroup\$ – Drew Sep 21 '20 at 3:03
  • \$\begingroup\$ @jonk I have looked at the datasheet of the rectifier, the max output is 40Amps and the load, in total, takes 11Amps. The other idea is to separately use two rectifier; each powering single load. How is that idea? \$\endgroup\$ – Sam Shurp Sep 21 '20 at 3:03

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