7PG2113/4/5/6 Solkor Description of Operation
4.7
Current Protection: Under-Current (37)
Two under-current elements are provided
37-1 & 37-2
.
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.
1
c
&
<
<
<
Figure 4.7-1 Logic Diagram: Relays with 4 Current Inputs Undercurrent Detector (37)
Figure 4.7-2 Logic Diagram: Relays with 1 Current Inputs Undercurrent Detector (37)
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