Current Protection: Under-Current (37); Figure 3.8-1 Logic Diagram: Undercurrent Detector (37) - Siemens 7SR224 Description & Operation

(1) Description of Operation 7SR224
3.8 C P : U -C (37)
URRENT ROTECTION NDER URRENT
Two under-current elements are provided.
Each phase has an independent level detector and current-timing element. 37-n Setting sets the pick-
up current. An output is given after elapse of the 37-n Delay setting.
Operation of the under-current elements can be inhibited from:
A binary or virtual input.
Inhibit 37-n
Figure 3.8-1 Logic Diagram: Undercurrent Detector (37)
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