SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/hamg-g7a01

What does a power supply bleeder resistor do?

It discharges the filter capacitors when power is removed.

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  1. It acts as a fuse for excess voltage
  2. It discharges the filter capacitors when power is removed ✔
  3. It eliminates ground loop current

Why: Filter capacitors can hold a charge after the supply is switched off. The bleeder resistor slowly drains that charge, so the supply is safer to work on.

Huh, didn't know that: A power supply filter network is built from capacitors and inductors.

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References

Answer: It discharges the filter capacitors when power is removed. Filter capacitors can hold a charge after the supply is switched off. The bleeder resistor slowly drains that charge, so the supply is safer to work on.

  1. NCVEC 2023-2027 General Class Pool and Syllabus (6th Errata, Feb 4 2026) ncvec.org/downloads/General%20Class%20Pool%20and%20Syllabus%202023-2027%20Public%20Release%20with%206th%20Errata%20Feb%204%202026.pdf
    It discharges the filter capacitors when power is removed
    Checked 2026-10-11.

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