What protections are used in a power transformer?

Question

Accepted Answer

Power transformers are protected by various mechanisms to ensure safe operation and prevent damage.

Overcurrent protection: Protects against excessive current flow.
Overvoltage protection: Safeguards against high voltage spikes.
Temperature monitoring: Prevents overheating by shutting down the transformer if temperature exceeds safe limits.
Buchholz relay: Detects internal faults such as insulation breakdown or oil leakage.
Pressure relief devices: Releases excess pressure to prevent explosion.
Differential protection: Compares input and output currents to detect internal faults.
Ground fault protection: Detects faults to ground and isolates the transformer.
Lightning arrestors: Protects against lightning strikes by diverting excess current.
Oil level monitoring: Ensures proper oil levels for cooling and insulation.
Gas monitoring: Detects abnormal gas levels that indicate internal faults.

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