ABB 615 series Technical Manual page 462

Section 4
Protection functions
456
function is blocked and the timers are reset. In the "Block TRIP output" mode, the function
operates normally but the TRIP output is not activated.
Timer
If the detected fault direction is opposite to the set directional mode and GFC release is
active, BLK_EF output is activated once Pickup delay time has elapsed. Reset timer is
activated at the falling edge of General Fault Criterion release, that is, when zero-sequence
voltage falls below Voltage pickup value. BLK_EF is reset once the reset delay time
elapses. Activation of the BLOCK input deactivates the BLK_EF output and resets Timer.
VG
IG
GFC release
Reset timer
BLK_EF
Reset delay time
Pickupt delay time
GUID-A2A55E4C-395C-43BB-A942-2991EA37E3A4 V1 EN
Figure 219: Activation of BLK_EF output (indication that fault is located opposite to
the set operate direction)
Pickup delay time
1MAC059074-MB A
Reset delay time
615 series ANSI
Technical Manual