Numerical Self Powered Protection Relay For RMU : ADR241S Specifications 4 Element (3 Phase + EF) over current IDMT with instant trip. Display of fault current. / Load current. Selection of Curve: Six selectable curves (Normal Inverse1 (C1), Normal Inverse2 (C2), Very Inverse (C3), Extremely Inverse (C4), Long Time Inverse (C5) & Definite Time (C6). Separate curve selection for phase and EF. Latching of fault current up-to last 5 fault. Programmable Annunciation Contact SCADA compatibility. IEC60870-5-103 protocol. The ADR241S is self powered relay, communicable 3 OC and 1 EF with Instantaneous high set specially designed for Protection of Ring Main Unit or compact sub-station where no any external power supply is not available.