Advanced Qualification · A-004 Power supplies · A-004-002-008
When using a choke input filter, a minimum current should be drawn all the time when the device is switched on. This can be accomplished by:
- A utilizing a full-wave bridge rectifier circuit
- B placing an ammeter in the output circuit
- C increasing the value of the output capacitor
- D including a suitable bleeder resistance
Correct answer: D — including a suitable bleeder resistance. From the official ISED question bank, verified word for word.
Why
Including a suitable bleeder resistance ensures a small, constant flow of current through the power supply even when no external device is connected. The full explanation — and one for every question — is in Pro.
Practise this section
Power supplies: rectifiers, filtering, regulation, switching supplies and their failure modes.