The role of InsuLogix® RFM is to provide a visible external indication when arcing occurs inside the transformer tank causing an over-pressure condition. The device’s red indicator serves as confirmation that a fault has occurred within the transformer, and the unit should not be re-energized for safety reasons. The InsuLogix® RFM is sensitive enough to detect a pressure increase due to internal low energy arcing which can result from partial discharge, or high energy arcing resulting from short circuits between phases or between phase and ground. InsuLogix® RFM is easy to maintain and comes equipped with a patent-pending pressure relief valve for the release of internal tank pressure manually or automatically.