ABB RELION REX640 Technical Manual page 1133

1MRS759142 C
REX640
Technical Manual
CB_CL_CMD
START
START_DLYD
I_A
I_B
I3P
I_C
U_A
U_B
U3P
U_C
BLOCK
GUID-531E0661-ABB1-46EC-AA6A-1721457CA132 V1 EN
Figure 610: Functional module diagram
Trigger
This module is used for detecting a possible fault immediately after circuit breaker
closing. The use of external protection function, typically the start signal from a non-
directional distance zone or overcurrent stage, is required for fault indication. The
START and START_DLYD inputs are available for the purpose.
• The START input has no delay. Thus, a switch-onto-fault situation is
immediately signalled to SOTF control.
• START_DLYD is used when an additional delay is required to start the signal. The
switch-onto-fault situation is signalled to the SOTF control after the set Operate
delay time.
Dead-line detector
The dead line detection should be used only when the voltage
transformers are located on the line side of the circuit breaker.
The Automatic SOTF Ini setting is used to configure the internal dead line detection
function.
Protection related functions
Trigger
SOTF
Dead-line
control
detector
SOTF
detection
Section 5
OPERATE
1127