A bleeder resistor is a normal resistor that, most often, is connected in parallel with a high voltage DC capacitor, or capacitor battery. This ensures that the voltage on the capacitors is discharged fast, when power is disconnected. A common situation could be a service on a UPS, where the high voltage f.ex. should be lower than 50V after max. 5 min. This is to minimize the risk of electric shock when the unit is opened by the service technician.
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