Electrical Engineering XYZ MCQs
The Buchholz relay is used for protecting transformer against:
- External faults
- Internal faults
- Both of these
- None of these
Correct answer: 2. Internal faults
Explanation:
- The Buchholz relay is a protective device specifically designed for oil-filled transformers. It is placed in the oil-filled pipe connecting the main tank and the conservator tank of the transformer.
- The primary purpose of the Buchholz relay is to detect and respond to internal faults that may occur within the transformer, such as a short circuit or insulation failure.
- The relay operates based on the principle that in the event of an internal fault, gas and oil generated within the transformer due to the fault will cause a flow of oil through the Buchholz relay. This flow triggers the relay to actuate alarms or initiate tripping of the transformer to prevent further damage.
- It is not designed to protect against external faults but is specifically intended to safeguard the transformer from faults originating within its internal components.
Therefore, the correct answer to the multiple-choice question is: Internal faults