How does a transformer oil level sensor monitor oil volume?

Oil level sensors measure the oil height in the tank or conservator and convert it to an electrical signal. Technologies include float type switches, magnetic reed sensors, capacitive probes, ultrasonic sensors, or pressure based measurement corrected for temperature. The sensor provides alarms for low or high level, which can indicate leaks, improper filling, or thermal expansion issues. When linked with temperature compensation and tank geometry, the system can estimate oil volume and support condition monitoring for slow leaks.