24kv Indoor Fixed type Mv Switchgear VCB Vacuum Circuit Breaker
General
The vacuum circuit-breakers of type VD4/S are intended for indoor installation in air-insulated switchgear systems. They have a switching capacity capable of handling the loads occurring at start-up and shutdown of equipment and plant units both in normal and in fault state.Vacuum circuit-breakers have particular advantages for use in networks where there is a high switching frequency in the working current range and/or where a certain number of short-circuit breaking operations are expected. Type VD4/S vacuum circuit-breakers are suitable for autoreclosing, and have exceptionally high operating reliability and long life. The vacuum circuit-breakers of type VD4/S, designed in column form, can be supplied both as individualunits for switchgear T ype SM6, Uniswitch, HXGN, etc.
The vacuum circuit-breakers of type VD4/S are intended for indoor installation in air-insulated switchgear systems. They have a switching capacity capable of handling the loads occurring at start-up and shutdown of equipment and plant units both in normal and in fault state.Vacuum circuit-breakers have particular advantages for use in networks where there is a high switching frequency in the working current range and/or where a certain number of short-circuit breaking operations are expected. Type VD4/S vacuum circuit-breakers are suitable for autoreclosing, and have exceptionally high operating reliability and long life. The vacuum circuit-breakers of type VD4/S, designed in column form, can be supplied both as individualunits for switchgear T ype SM6, Uniswitch, HXGN, etc.
Main Technical Datas
| No. | Item | Unit | Parameters | |
| 1 | Rated voltage | kV | 12/17.5 | 24 |
| 2 | Rated frequency | Hz | 50/60 | |
| 3 | Rated current | A | 630/800/1250/1600 | |
| 4 | 1min Power frequency withstand voltage | kV | 38/42/45 | 50 |
| 5 | Lightning impulse withstand voltage | kV | 75/95 | 125/150(*) |
| 6 | Rated short circuitbreaking current (peak) | kA | 50/63/80 | |
| 7 | Rated shortbreaking current | kA | 20/25/31.5 | |
| 8 | Rated short circuit making current (peak) | kA | 50/63/80 | |
| 9 | Cable chargebreaking current in earthing fault | A | 20 | 20 |
| 10 | Rated withstand current (peak) | kA | 50/63/80 | |
| 11 | Short time withstand current (4s) | kA | 20/25/31.5 | |
| 12 | Mechanism life | times | 10000 | |
| 13 | Operation sequence | O-0.3-CO-180S-CO | ||
| 14 | Rateof riseof transient recovery voltage | kV/uS | 0.34/0.42 | 0.47 |
| 15 | Peak of transient recovery voltage | kV | 20.6/30 | 41 |
