Buchholz Relay

The gas and oil actuated (Buchholz) relay is designed to detect faults as well to minimize the propagation of any damage which might occur within oil-filled transformers, capacitors and reactors supplied with oil

The relay is therefore particularly effective in case of:
1. Short-circuited core laminations
2. Broken-down core bolt insulation
3. Bad contacts
4. Overheating of some part of the windings
5. Short-circuits between phases
6. Earth faults puncture of bushing insulators inside tank

Furthermore the relay can prevent the development of conditions leading to a fault in the transformer, such as the falling of the oil level owing to leaks, or the ingress of air as a result of defects in the oil circulating system.