The Oil Level Indicator (OLI) was developed in response to the need of maintenance professionals to gauge the oil level inside large tanks, gearboxes and reservoirs. The OLI is a clear high performance polyamide column with 1/2″ NPT threads at each end.

What is oil level indicator in transformer?

The oil level indicator displays if air bubbles have remained in the transformer, if gas has been generated because of an internal failure or if there is a leakage at the transformer tank.

What is an oil level gauge?

Oil gauges look like most indicators on your dashboard. There's a label (typically “OIL”), numbers (ranging between 1-80 or 1-100), and a dial with an indicator needle. Instead of numbers, some vehicles use "L" and "H" to indicate high or low pressure.