Improvements in or relating to the protection of power transformers

Abstract

A method of protecting a power transformer including: monitoring an external fault indication signal; carrying out locally a fault determination; carrying out locally an inrush current determination; and issuing a final trip signal to protect the power transformer if the external fault indication signal identifies that a fault has occurred and the locally carried out fault determination confirms that a fault has occurred; or the external fault indication signal identifies that a fault has occurred and the locally carried out fault determination identifies that no fault has occurred but after a predetermined delay the locally carried out inrush current determination confirms the absence of an inrush current.

Dependencies are inferred from the claim text.