Toshiba GR200 Series - 2.20.5 Operation timing

6F2S1914 (0.49)
GRL200 (Soft 033 & 037)
- 297 -
2.20.5 Operation timing
The OCCBF and EFCBF elements can check that the target CB has opened normally and that
the fault current has disappeared completely. Because load current is usually present, the
OCCBF and EFCBF settings should be account for between 10% and 200% of the rated current.
The time settings [TCBF1-RE] and [TCBF1-TP] are determined in relation to the opening
time of the target CB and the reset time of the OCCBF or EFCBF elements (see Toc and Tcb
in Figure 2.20-1). The following description illustrates a setting calculation example when “re-
trip” is used:
Setting of TCBF-RE =Breaker opening time + OCCBF/EFCBF reset time + Margin
=40ms + 10ms + 20ms
=70ms
Setting of TCBF-TP =TCBF-RE + Output relay operating time + Breaker opening time +
OCCBF/EFCBF reset time + Margin
=70ms + 10ms + 40ms + 10ms + 10ms
=140ms