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

7SR224 Argus Description of Operation
3.8 Current Protection: Under-Current (37)
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:
Inhibit 37-n A binary or virtual input.
IL1
1
37-n
37-n Delay
Inhibit 37-n
37-n Setting
c
&
37-n
Enabled
Disabled
<
<
<
IL2
IL3
Figure 3.8-1 Logic Diagram: Undercurrent Detector (37)
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