Sensitive Earth Fault (67/50S,67/51S); Figure 2-9 Sensitive Earth Fault - Siemens 7SR21 Manual

2.8

Sensitive Earth fault (67/50S,67/51S)

Voltage Inputs:
Current Inputs:
Disable:
Map Pickup LED:
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, Sensitive EF & Restricted EF protections can be
Enabled/Disabled individually or as groups in the 'Function Config' menu.
Sensitive EF elements can be separated from Derived EF and Measured EF by secondary injection of current
through the I input circuit only.
5
If any of these elements are defined as directional the correct voltage phase direction will be required to produce
an operation of those elements.
©2010 Siemens Protection Devices Limited
7SR21 & 7SR22 Argus Commissioning and Maintenance

Figure 2-9 Sensitive Earth Fault

V (V ), V (V ), V (V ) for directional elements
L1 A L2 B L3 C
I (I )
5 SEF
64H, 50CBF, 79
51SEF-n/50SEF-n - Self Reset
Chapter 6 Page 33 of 69