Siemens 7SR242 - Open Circuit (46 BC); Figure 3-12 Logic Diagram: Open Circuit Function (46 BC)

7SR242 Duobias Description Of Operation
©2010 Siemens Protection Devices Limited Chapter 1 Page 32 of 52
3.6 Open Circuit (46BC)
Optionally two open circuit elements are provided, each can be selected to either winding 1 or winding 2.
The element calculates the ratio of NPS to PPS currents. Where the NPS:PPS current ratio is above 46BC
Setting an output is given after the 46BC Delay.
The Open Circuit function can be inhibited from
Inhibit 46BC A binary or virtual input .
Gn 46BC-n U/I Guarded Operation of the undercurrent guard function.
Inhibit 46BC
46BC
46BC Element
Enabled
Disabled
c
&
46BC Setting
IL1
IL2
IL3
NPS
Filter
I2
PPS
Filter
I1
46BC Delay
46BC-n U/I
Guarded
Yes
<
46BC-n U/I
Guard Setting
&
&
<
<
Figure 3-12 Logic Diagram: Open Circuit Function (46BC)