Measured Earth Fault (67/50G,67/51G); Figure 2-8 Measured Earth Fault - Siemens 7SR21 Manual

2.7

Measured Earth fault (67/50G,67/51G)

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.
Measured EF elements can be separated from Derived EF and Sensitive EF by secondary injection of current
through the I input circuit only.
4
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 2-8 Measured Earth Fault

V (V ), V (V ), V (V ) for directional elements
L1 A L2 B L3 C
I (I )
4 G
50CBF, 79
51G-n/50G-n - Self Reset
Chapter 6 Page 29 of 69