7PG2113/4/5/6 Solkor Description of Operation
4.3.2 Instantaneous Measured Earth Fault Protection (50G)
Two instantaneous derived earth fault elements are provided in the 7PG2113/5 relay and four elements are
provided in the 7PG2114/6 relay.
50G-1, 50G-2, (50G-3 & 50G-4 – 7PG2114/6)
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.
Where directional elements are present the direction of operation can be set using
50G-n Dir. Control
setting.
Directional logic is provided independently for each 50G-n element e.g. giving the option of using two elements
set to forward and two to reverse.
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: 50G-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 (7PG2114/6).
Figure 4.3-2 Logic Diagram: Measured Instantaneous Earth-fault Element
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