ABB Relion 670 Series Technical Reference Manual page 670

Section 12
Control
664
no outputs are generated, no reporting, control commands are rejected and
functional and configuration data is visible.
The different block conditions will only affect the operation of this
function, that is, no blocking signals will be "forwarded" to other
functions. The above blocking outputs are stored in a non-volatile
memory.
Interaction with synchronism-check and synchronizing functions
The Switch controller (SCSWI) works in conjunction with the synchronism-check and
the synchronizing function (SESRSYN, 25). It is assumed that the synchronism-check
function is continuously in operation and gives the result to SCSWI. The result from
the synchronism-check function is evaluated during the close execution. If the operator
performs an override of the synchronism-check, the evaluation of the synchronism-
check state is omitted. When there is a positive confirmation from the synchronism-
check function, SCSWI will send the close signal EXE_CL to the switch function
Circuit breaker (SXCBR).
When there is no positive confirmation from the synchronism-check function, SCSWI
will send a start signal START_SY to the synchronizing function, which will send the
closing command to SXCBR when the synchronizing conditions are fulfilled, see
figure 331. If no synchronizing function is included, the timer for supervision of the
"synchronizing in progress signal" is set to 0, which means no start of the
synchronizing function. SCSWI will then set the attribute "blocked-by-synchronism-
check" in the "cause" signal. See also the time diagram in figure 335.
1MRK505222-UUS C
Technical reference manual