What types of protection mechanisms are used in transformers?

Question

Accepted Answer

Transformers use various protection mechanisms to ensure safe operation and prevent damage from faults.

Overcurrent Protection: Uses fuses or circuit breakers to disconnect the transformer during overload conditions.
Differential Protection: Detects differences in current between primary and secondary windings to identify faults.
Bushing Insulation Protection: Monitors the insulation condition of transformer bushings to prevent failures.
Temperature Protection: Uses temperature sensors to monitor winding and oil temperatures, triggering alarms or shutdowns if limits are exceeded.
Pressure Relief Devices: Protects against internal pressure build-up due to faults or overheating by venting excess pressure.

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