Siemens 7SR18 Solkor - Instantaneous Measured Earth Fault Protection (50 G); Figure 3.5.2-1 Logic Diagram: Measured Instantaneous Earth-Fault Element

7SR18 Description Of Operation
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3.5.2 Instantaneous Measured Earth Fault Protection (50G)
Up to four instantaneous derived earth fault elements are provided in the relay (depending upon variant): -
50G-1, 50G-2, 50G-3 & 50G-4
Each instantaneous element has independent settings for pick-up current 50G-n Setting and a follower time
delay 50G-n Delay. The instantaneous elements have transient free operation.
Operation of the instantaneous measured earth fault elements can be inhibited from:
Inhibit 50G-n A binary or virtual input.
79 E/F Inst Trips: 51N-n When ‘delayed’ trips only are allowed in the auto-reclose sequence
(79 E/F Prot’n Trip n = Delayed).
50-n Inrush Action: Block Operation of the inrush current detector function.
50G-n VTSAction: Inhibit Operation of the VT Supervision function
Figure 3.5.2-1 Logic Diagram: Measured Instantaneous Earth-fault Element