Auto Reclose Blocking Scheme
1. AR shall not be intiated under line is connected with generator bus unless proper analizes in the fulty line.
2. In case genarating power plant bus is connected to grid by medium and long lines,high-speed auto reclosing can be intiated by reverse direction (first chargeing the line from remote end and then reclose the CB at power plant end) for lines which restict the fult current to such a level that maximum shaft torques are with in the genarator specification under fault conditions.
3. AR shall not be intiated under the following conditions
a. BFP, BB protection trips
b. Direct transfer receiving Trips ( BF,PD)
c. SOTF Trips
d. Time delay trip
e. All type of communication failures ( 21 , 87L, BF,PD)
f. Both line & Bus side VT fuse failures
AR operate only zone -1 Ground to Earth Fault