Product Description
If it becomes milky white from its original finish of silvery mirror then it indicates that the baffle is losing its vacuum. A sputter shield, usually, made of stainless steel, is placed between the contacts and the envelope in order to prevent the metal vapour reaching the envelope as it reduces the breakdown strength between the contacts. Inside the sputter shield the breaker has two contacts, one fixed and the other moving contact.
The moving contact moves through a short distance of 5 to 10 mm depending upon the operating voltage. The metallic bellows made of stainless steel is used to move the lower contact. The design of the bellows is very important because the life of the vacuum breaker depends upon the ability of this component to perform repeated operations satisfactorily. The periphery of the end-cap is sealed to the envelope and the fixed contact stem is an integral part of one end-cap. One end of the fixed as well as moving contact is brought out of the chamber for external connections.
| Item | Unit | Data |
| Rated voltage | KV | 12 |
| Maximum working voltage | KV | 12 |
| Rated Current | A | 630-1250 | 630-1600 | 630-1600 |
| Rated short circuit breaking current | KA | 20 | 25 | 31.5 |
| Rated short-circuit switching current | KA | 50 | 63 | 80 |
| Rated peak withstand current | KA | 50 | 63 | 80 |
| 4S rated short-circuit withstand current | KA | 20 | 25 | 31.5 |
| Rated insulation level | 1min Power frequency withstand voltage | KV | 42(fracture 48) |
| lmpulse withstand voltage | KV | 75(fracture 84) |
| Rated short-circuit current breaking times | Times | 50 |
| Rated Operating Mechanism Closing Voltage(DC) | V | AC,DC 110,220 |
| Rated Operating Mechanism Opening Voltage(DC) | V | AC,DC 110,220 |
| Contact opening distance | mm | 11±1 |
| Overtravel(the length of contact spring compression) | mm | 3.5±0.5 |
| Closing/Opening Time Difference Among Three Phase | ms | ≤2 |
| Contact closing bounce time | ms | ≤2 |
| Average opening speed | m/s | 0.9-1.2 |
| Average closing speed | m/s | 0.5-0.8 |
| Tripping Time | Maximum operating voltage | S | ≤0.05 |
| Minimum operating voltage | S | ≤0.08 |
| Closing time | S | 0.1 |
| The main circuit resistance of each phase | | 630≤50 | 1250≤45 | 1600≤40 |
| Allowed Consumpted thickness of Contacts | mm | 3 |
XK 11kv insulated high voltage 3 phase pole mounted vacuum circuit breaker vcb
