Measured Earth Fault Protection (50G); Figure 3-14 Logic Diagram: Measured Instantaneous Earth-Fault Element - Siemens 7SR17 Rho Manual

3.4.2

Measured Earth Fault Protection (50G)

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
Gn 50G-n Element
Disabled
Enabled
EF In
Inhibit 50G-n
50G Measurement
I
G
50G-n Dir
Control
Non Dir
Forward
Reverse
67G Fwd
67G Rev
Figure 3-14
©2014 Siemens Protection Devices Limited
A binary or virtual input
&
Gn 50G-n Setting
En
>
Dir En En
50G-n VTS
Action
Non Dir
Inhibit
VT Fail
&
1
&
If directional elements are not present this
block is omitted and 'Dir En' signal is set TRUE.
Logic Diagram: Measured Instantaneous Earth-fault Element
Chapter 1) 7SR17 Rho Description Of Operation
Gn 50G-n Delay
& &
50G-n Dir En
& 1
General Pickup
50G-n
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