| Place of Origin: | Zhejiang, China |
|---|---|
| Brand Name: | XK |
| Certification: | ISO9001 / GB / IEC |
| Model Number: | ZW7A-40.5 |
| Minimum Order Quantity: | 1 Piece/Pieces |
| Price: | Negotiation |
| Packaging Details: | EXPORTING PACKING |
| Supply Ability: | 100 Piece/Pieces per Month |
| Name: | Vacuum Circuit Breaker | Standard: | IEC |
|---|---|---|---|
| Rated Current: | 1250A, 1600A | Rated Voltage: | 40.5KV |
| Mechanical Life: | 10000 | Port: | NINGBO |
| High Light: | vcb circuit breaker,outdoor vcb breaker |
||
| Item | Unit | Data |
| Rated frequency | Hz | 50,60 |
| Power frequency with stand voltage 1min(wet)(dry) phase to ground/fracture | KV |
80 95/95
|
| Lightning impulse with stand voltage | KV | 185 |
| Rated short circuit breaking current | KA | 25/31.5 |
| Rated short circuit witch ingcurrent | KA | 63/80 |
| Rated peak with stand current | KA | 63/80 |
| 4S short time with stand current | KA | 25/31.5 |
| Rated short circuit breaking times | times |
30
|
| Control voltage of mechanism | V | AC/DC 220 |
| Second ary circuit power frquency with stand voltage 1min | KV | 2 |
| Contact opening distance | mm | 18±1 |
| Contact over-travelling distance | mm | 4±0.5 |
| Opening speed | m/s | 1.4-1.8 |
| Closing speed | m/s | 0.4-0.8 |
| Contact closing bounce time | ms | ≤5 |
| Middled is tance between phases | mm | 700±2 |
| Closing/Opening time difference between three phases | ms | ≤2 |
| The circuit esistance of each phase | Ω | <80 |
| Closing time | ms | ≤100 |
| Opening time | ms | ≤50 |
| Weight | KG | 500 |
All circuit breaker systems have common features in their operation, but details vary substantially depending on the voltage class, current rating and type of the circuit breaker.
The circuit breaker must first detect a fault condition. In small mains and low voltage circuit breakers, this is usually done within the device itself. Typically, the heating or magnetic effects of electric current are employed. Circuit breakers for large currents or high voltages are usually arranged with protective relay pilot devices to sense a fault condition and to operate the opening mechanism. These typically require a separate power source, such as a battery, although some high-voltage circuit breakers are self-contained with current transformers, protective relays, and an internal control power source.
Once a fault is detected, the circuit breaker contacts must open to interrupt the circuit; this is commonly done using mechanically stored energy contained within the breaker, such as a spring or compressed air to separate the contacts. Circuit breakers may also use the higher current caused by the fault to separate the contacts, such as thermal expansion or a magnetic field. Small circuit breakers typically have a manual control lever to switch off the load or reset a tripped breaker, while larger units use solenoids to trip the mechanism, and electric motors to restore energy to the springs.
The circuit breaker contacts must carry the load current without excessive heating, and must also withstand the heat of the arc produced when interrupting (opening) the circuit. Contacts are made of copper or copper alloys, silver alloys and other highly conductive materials. Service life of the contacts is limited by the erosion of contact material due to arcing while interrupting the current. Miniature and molded-case circuit breakers are usually discarded when the contacts have worn, but power circuit breakers and high-voltage circuit breakers have replaceable contacts.
When a high current or voltage is interrupted, an arc is generated. The length of the arc is generally proportional to the voltage while the intensity (or heat) is proportional to the current. This arc must be contained, cooled and extinguished in a controlled way, so that the gap between the contacts can again withstand the voltage in the circuit. Different circuit breakers use vacuum, air, insulating gas, or oil as the medium the arc forms in. Different techniques are used to extinguish the arc including:
Lengthening or deflecting the arc
Intensive cooling (in jet chambers)
Division into partial arcs
Zero point quenching (contacts open at the zero current time crossing of the AC waveform, effectively breaking no load current at the time of opening. The zero-crossing occurs at twice the line frequency; i.e., 100 times per second for 50 Hz and 120 times per second for 60 Hz AC.)
Connecting capacitors in parallel with contacts in DC circuits.
Finally, once the fault condition has been cleared, the contacts must again be closed to restore power to the interrupted circuit.
