- Control Unit:
Electrical control giving the necessary timing function for the operation of the sectionalizer.
The sectionalizer always performs its isolating function in coordination with the operation of the recloser in a substation by these operation:
- The recloser at the sub-station will always interrupt short-circuit or earth fault of the distribution line
- As no voltage condition is impressed on the control unit of the sectionalizers, they will open automatically after a time delay of 2s in case of interruption of the circuit
- The sectionalizer will close automatically one by one with a time interval of 10s from the substation side to the end of the distribution line.
- After the sectionalizer closes, the eliminating time of the control unit starts. If a fault occurs, and the recloser opens during the eliminating time, the sectionalizer will open and will be locked out
- The sectionalizer will lock-out only if no voltage occurs during the eliminating time
- In fault of permanent nature, the recloser at the substation will interrupt again, when the sectionalizer that is faulty closes.
Figure show sectionalizer & recloser configuration in grid