Concept:Filter capacitors in high-voltage supplies can retain lethal electrical charge long after power is disconnected. A bleeder resistor connected across the capacitor provides a discharge path to safely dissipate this stored energy when power is turned off.
Formula:$$v_C(t) = V_{\text{initial}} \exp\left(-\frac{t}{R_{\text{bleeder}} C}\right) \longrightarrow 0\text{ V}$$
Solution:- When power is disconnected from an unloaded supply, high-voltage capacitors can hold dangerous charge for hours.
- A bleeder resistor provides a continuous discharge path (\( \tau = R_{\text{bleeder}} C \)) that drains stored voltage within seconds of shutdown.
- It also provides a small minimum load current that improves output voltage regulation.
Why other options are incorrect:- Option A: Bleeder resistors do not increase ripple.
- Option C: A parallel resistor does not change the rectifier topology.
- Option D: A bleeder resistor does not replace equipment safety ground requirements.
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