Siemens 7SR242 Duobias - 2.3 Measured Earth fault (50 G, 51 G)

7SR242 Duobias Commissioning & Maintenance Guide
©2010 Siemens Protection Devices Limited Chapter 6 Page 24 of 57
2.3 Measured Earth fault (50G, 51G)
Figure 2-5 Measured Earth Fault
Voltage Inputs: None
Current Inputs: I
G1 ,
I
G2
Disable: 50BF, 64H
Map Pickup LED: 51G-n/50G-n - Self Reset
Other protection functions may overlap with these functions during testing, it may be useful to disable some
functions to avoid ambiguity. Derived EF, Measured EF & Restricted EF protections can be Enabled/Disabled
individually or as groups in the ‘Function Config’ menu.
These elements can be allocated to I
G1
or I
G2
current inputs by relay settings, ensure that current is injected on
the correct input.
Measured EF elements can be separated from Derived EF by secondary injection of current through the I
G1
or I
G2
input circuit only.