Setting Notes - Siemens 7SC80 Manual

Functions
2.18 Breaker Failure Protection 50BF
[7sj80-svs-20061219, 2, en_US]
Figure 2-107

Setting Notes

2.18.2
General
Breaker failure protection is only effective and accessible if address 170 50BF is set to Enabled or enabled
w/ 3I0>. Setting Enabled considers the three phase currents for total current monitoring. Setting enabled
w/ 3I0> additionally evaluates the ground current or the negative sequence system when only one phase
current occurs.
With the setting Enabled w/o I>, only the circuit breaker auxiliary contacts are evaluated. The current crite-
rion CB Icrit.closed is not included in the logic (see
If this function is not required, then Disabled is set. The function can be set to ON or OFF under address
7001 FCT 50BF.
320
Logic diagram of the breaker failure protection
Figure 2-105).
E50417-G1140-C486-A8, Edition 07.2017
SIPROTEC Compact, 7SC80, Manual