Design Considerations
There is always a trade-off between the speed with which the bleeder operates and the amount of power wasted in the bleeder; a lower resistance value results in a faster bleed-down rate but wastes more power during normal, power-on operation.
The presence of a bleeder also guarantees a minimum load on the power source, which can help reduce the range of voltage change (regulation) when the normal load is changing and there is no active regulator. Use of a bleeder this way is a common design strategy for power supplies of vacuum tube power amplifiers, for instance.
Large capacitors can actually recover a substantial part of their charge after being discharged by the bleeder resistor, if the resistor is not left in place. This is due to a property called dielectric absorption, in which energy stored in the dielectric during use is released gradually over time. Therefore the bleeder should ideally be connected permanently.
Read more about this topic: Bleeder Resistor
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