Load Break Switch
The FZN25 and FZRN25 series vacuum load switches and combined electrical appliances are suitable for load control and short-circuit protection in three-phase AC 50Hz ring networks or terminal power supplies and industrial electrical equipment. The load switches connect and disconnect loads, closed-loop current, and unloaded transformer and cable charging current. The combined electrical appliances can interrupt any current up to the rated short-circuit current. They employ direct-acting isolation contacts and vacuum arc chamber linkage. Both manual and electric functions are available.
The unique transmission structure design of FZN25 and FZRN25 ensures that the arc-extinguishing chamber only bears high pressure at the moment of closing and opening, resulting in a small size and light weight. FZN25 and FZRN25 can achieve one-time operation of the isolation break and the arc-extinguishing chamber break.
The FNZ25 and FZRN25 have a grounding valve between the stationary contact and the conductive cylinder of the moving contact, which is linked to the grounding switch, ensuring both safety and convenient maintenance.
Manufacturer data — model designation, technical parameters, dimensions and installation details.
FZRN25-12D/125-31.5 Vacuum Load Switch-Fuse Combination Appliance Outline and Installation Dimensions (mm)
| Project | Unit | Parameter | |
|---|---|---|---|
| FZN25-12D/T630-20 | FZRN25-12D/T125-31.5 | ||
| Rated voltage | kV | 12 | |
| Rated frequency | HZ | 50 | |
| Rated current | A | 630 | 125 |
| Rated insulation level | 1-minute power frequency withstand voltage | kV | Arc-extinguishing chamber fracture 30; to ground, phase-to-phase 42; isolation fracture 48 |
| Lightning impulse withstand voltage | kV | Ground-to-ground, phase-to-phase 75: isolation break 85 | |
| Rated dynamic current (peak) | KA | 50 | - |
| 4S thermally stable current | KA | 20 | - |
| Rated active load breaking current | A | 630 | 125 |
| Rated closed-loop breaking current | A | 630 | 125 |
| Rated cable charging breaking current | A | 10 | 10 |
| Breaking off no-load transformer capacity | kVA | 1250 | 1250 |
| Rated short-circuit breaking current | KA | - | 31.5 |
| Rated transfer current, rated handover current | A | - | 2000 |
| Fuse model | - | SDLAJ-12 SFLAJ-12 | |
| Impactor output energy | J | - | 2-5(中等) |
| Rated short-circuit making current | KA | 50 | |
| Rated dynamic stability current of grounding switch | KA | 50 | |
| Grounding switch 2S thermal stability current | KA | 20 | |
| Auxiliary circuit rated voltage | V | AC/CD :220/110 | |
| Mechanical life | 次 | 10000 |
