Vacuum circuit-breakers of series BP type BP3 are designed for switching electrical circuits in normal and emergency modes in three-phase alternating current networks of 50 (60) Hz frequency and 10 kV rated voltage for ungrounded or partially grounded neutral systems. Circuit-breakers are used in newly designed complete switchgears as well as for reconstruction of switchgear cubicles in use (in any cases BP circuit-breakers should be installed only by agreement with the manufacturer).
Specifications:
- Rated voltage (kV): 10
- Rated current (A): 2000-3150
- Rated breaking capacity (kA): 31.5, 40
- Peak withstand current (kA): 80, 102
- Mechanical lifetime: 30000 CO cycles
- Electrical lifetime: 30000 CO cycles
- Electrical lifetime at rated breaking current: 50 O cycles
Design
All circuit-breakers series BP type BP3 consist of three poles with vacuum interrupters filled with cast epoxy compound. In versions rated for 2500 A and 3150 A currents vacuum interrupters and terminals are installed on insulating supports. The circuit-breaker electromagnetic drive fixing circuit-breakers in C and O positions on magnetic latches is housed in the circuit-breaker frame. The core of the electromagnetic drive is connected with the circuit-breaker shaft via connecting links. The circuit-breaker shaft is connected via insulating tie-rods with vacuum interrupters and when turning, it controls circuit-breaker position contacts for external auxiliary circuits. In circuit-breakers rated for 2500 A and 3150 A currents, pole tie-rods are fitted with groups of coiled pressing springs. The local manual emergency switching-off of the circuit-breaker is actuated by a separate switching-off lever, which is common for all types of BP circuit-breakers. Control block schemes are realized by using PCBs housed in circuit-breakers series BP.
The vacuum circuit-breaker control block (scheme) is housed in the circuit-breaker frame. The control is carried out both by AC and DC. The circuitry realised in the control block makes it possible to easily use circuit-breakers for all well-known common operations in circuits with spring drive and electromagnetic drive for all new and formerly manufactured complete switchgears (К-IIIu, К-XII, К-ХXVI, К-37, KRU2-10, К-59, К-104, КМ-1F, КU-10C, К-Х and others).