Common use of Circuit Breakers (GIS Clause in Contracts

Circuit Breakers (GIS. GIS Circuit breakers shall in general be of C2-M2 class and comply to IEC-62271-100. The rated break time shall not exceed 40 ms (milli second) for 765 kV and 400 kV. Circuit breakers shall be suitable for single phase and three phase auto reclosing. Each breaker would have two sets of trip circuits which would be connected to separate DC supplies for greater reliability. The Circuit breakers controlling 765 kV lines shall be provided with pre- insertion closing resistor of about 450 ohms with 9 ms insertion time or Controlled Switching Device (CSD). The Circuit breakers controlling 400 kV lines wherever required shall be provided with pre-insertion closing resistor of about 400 ohms with 8 ms insertion time or Controlled Switching Device (CSD) for lines longer than 200 km. The short line fault capacity shall be the same as the rated capacity and this is proposed to be achieved without use of opening resistors. Controlled switching device shall be provided in the Circuit Breaker of the switchable line reactor bay and in Main and Tie bay circuit breakers of line with non-switchable line reactors, Bus reactors and Transformers for 400 kV and above voltage class.

Circuit Breakers (GIS. GIS Circuit breakers shall in general be of C2-M2 class and comply to with IEC-62271-100. The rated break time shall not exceed 40 ms (milli second) for 765 kV and 400 kV. Circuit breakers shall be suitable for single phase and three phase auto reclosing. Each breaker would shall have two sets of trip circuits which would be connected to separate DC supplies for greater reliability. The Circuit breakers controlling 765 kV lines shall be provided with pre- pre-insertion closing resistor of about 450 ohms with 9 ms insertion time or Controlled Switching Device (CSD). The Circuit breakers controlling 400 kV lines wherever required shall be provided with pre-insertion closing resistor of about 400 ohms with 8 ms insertion time or Controlled Switching Device (CSD) for lines longer than 200 km. The short line fault capacity shall be the same as the rated capacity and this is proposed to be achieved without the use of opening resistors. Controlled switching device shall be provided in the Circuit Breaker of the switchable line reactor bay and in 400 kV and above Main and Tie bay circuit breakers of line with non-switchable line reactors, Bus reactors and Transformers for 400 kV and above voltage classTransformers.

Circuit Breakers (GIS. GIS Circuit breakers shall in general be of C2-M2 class and comply to IEC-62271-100. The rated break time shall not exceed 40 ms (milli second) for 765 kV and 400 kV. 765kV & 400kV. Circuit breakers shall be suitable for provided with single phase and three phase auto reclosing. Each breaker would have two sets of trip circuits which would be connected to separate DC supplies for greater reliability. The Circuit breakers controlling 765 kV 765kV lines shall be provided with pre- pre insertion closing resistor of about 450 ohms with 9 ms insertion time or Controlled Switching Device (CSD). The Circuit breakers controlling 400 kV 400kV lines wherever required shall be provided with pre-pre insertion closing resistor of about 400 ohms with 8 ms insertion time or Controlled Switching Device (CSD) for lines longer than 200 km. The short line fault capacity shall be the same as the rated capacity and this is proposed to be achieved without use of opening resistors. Controlled Control switching device shall be provided in the Circuit Breaker of the switchable line reactor bay and in Main and & Tie bay circuit breakers of line with non-non- switchable line reactors, Bus reactors and Transformers for 400 kV and above voltage class765/400kV Transformers.

Circuit Breakers (GIS. GIS Circuit breakers shall in general be of C2-M2 class and comply to IEC-62271-with IEC-62271- 100. The rated break time shall not exceed 40 ms (milli second) for 765 kV and 400 kV. 765kV and400kV. The rated break time shall not exceed 60 ms for 220kV. Circuit breakers shall be suitable for provided with single phase and three phase auto reclosing. Each breaker would shall have two sets of trip circuits which would be connected to separate DC supplies for greater reliability. The Circuit breakers controlling 765 kV 765kV lines shall be provided with pre- pre-insertion closing resistor of about 450 ohms with 9 ms insertion time or Controlled Switching Device (CSD). The Circuit breakers controlling 400 kV 400kV lines wherever required shall be provided with pre-insertion closing resistor of about 400 ohms with 8 ms insertion time or Controlled Switching Device (CSD) for lines longer than 200 km. The short line fault capacity shall be the same as the rated capacity and this is proposed to be achieved without use of opening resistors. Controlled switching device shall be provided in the Circuit Breaker of the switchable line reactor bay and in Main and & Tie bay circuit breakers of line with non-non- switchable line reactors, Bus reactors and Transformers for 400 kV and & above voltage class.

Circuit Breakers (GIS. GIS Circuit breakers shall in general be of C2-M2 class and comply to IEC-62271-100. The rated break time shall not exceed 40 ms (milli second) for 765 kV and 400 kV. Circuit breakers shall be suitable for single phase and three phase auto reclosing. Each breaker would have two sets of trip circuits which would be connected to separate DC supplies for greater reliability. The Circuit breakers controlling 765 kV lines shall be provided with pre- pre-insertion closing resistor of about 450 ohms with 9 ms insertion time or Controlled Switching Device (CSD). The Circuit breakers controlling 400 kV lines wherever required shall be provided with pre-insertion closing resistor of about 400 ohms with 8 ms insertion time or Controlled Switching Device (CSD) for lines longer than 200 km. The short line fault capacity shall be the same as the rated capacity and this is proposed to be achieved without use of opening resistors. Controlled switching device shall be provided in the Circuit Breaker of the switchable line reactor bay and in Main and Tie bay circuit breakers of line with non-switchable line reactors, Bus reactors and Transformers for 400 kV and above voltage class.

Circuit Breakers (GIS. GIS Circuit breakers shall in general be of C2-M2 class and comply to IEC-62271-100. The rated break time shall not exceed 40 ms (milli second) for 765 kV and 400 kV. Circuit breakers shall be suitable for single phase and three phase auto reclosing. Each breaker would have two sets of trip circuits which would be connected to separate DC supplies for greater reliability. The Circuit breakers controlling 765 kV lines shall be provided with pre- pre-insertion closing resistor of about 450 ohms with 9 ms insertion time or Controlled Switching Device (CSD). The Circuit breakers controlling 400 kV lines wherever required shall be provided with pre-insertion closing resistor of about 400 ohms with 8 ms insertion time or Controlled Switching Device (CSD) for lines longer than 200 km. The short line fault capacity shall be the same as the rated capacity and this is proposed to be achieved without use of opening resistors. Controlled switching device shall be provided in the Circuit Breaker of the switchable line reactor bay and in Main and Tie bay circuit breakers of line with non-non- switchable line reactors, Bus reactors and Transformers for 400 kV and above voltage class.