Figure 3-13 Logic Diagram: 7Sr12 Sef Instantaneous Element - Siemens 7SR12 Argus Manual

7SR11 & 7SR12 Description Of Operation
50SEF-n Dir.
Control
Non-Dir
Forward
Reverse
67SEF Fwd
67SEF Rev
50SEF-n Element
Disabled
Enabled
AUTORECLOSE
Inhibit 50SEF-n
79 P/F Inst Trips
= 50SEF-n
&
79 P/F Prot'n Trip n
= Delayed
Wattmetric Block
3I cos(θ-θ
0

Figure 3-13 Logic Diagram: 7SR12 SEF Instantaneous Element

Chapter 1 Page 44 of 88
&
&
I (I )
4 SEF
V
0
Inhibit Wattmetric
&
50SEF-n Dir En
Ires Select
I (I )
Ires
4 SEF
)
Ires Real
c
50SEF-n VTS Action
Off
Non-Dir
Inhibit
&
VT Fail
1 &
Wattmetric
67SEF Charact.angle
67SEF Wattmetric Power
>
Compensated
angle
50SEF-n Setting
c
>
©2017 Siemens Protection Devices Limited
&
1
50SEF-n Dir En
Wattmetric Block
3I cos(θ-θ )
0 c
General Pickup
50SEF-n Delay
50SEF-n