Claire
Mr.Fu
Claire
China FZN25-12 Indoor AC High-Voltage Vacuum Load Switch - 12kV, 630A, Reliable Factory Supplier
Type & Meaning
| F | Load Break Switch |
| Z | Vacuum |
| N | Indoor |
| 25 | Design Serial Number |
| 12 | Rated Voltage (kV) |
| D | Earthing Switch (Optional) |
| T | Spring Operating Mechanism |
| 630 | Rated Current (A) |
| 20 | Rated Short-time Withstand Current (kA) |
Basic Structure
The FZN25-12 is a frame-assembled load break switch. Moving/fixed contacts in each phase are enclosed in a vacuum interrupter, mounted with conductors on an integral insulator. The interrupter connects to a rear vertical disconnector via conductors. The disconnector is housed in a semi-enclosed insulator fixed to the metal frame. A side-mounted spring operating mechanism extends service life. A removable fuse assembly forms a switch-fuse combination. The frame includes an earthing arm, mechanism, and interlocks. A transparent flame-retardant shield ensures safety, and a bottom earthing contact enables integrated earthing switch versions.
- Uses vacuum interrupter for strong arc extinction, reliable and safe performance.
- Integrated load break switch, disconnector, and mechanism for simple one-step operation with visible break; optional earthing switch with interlock.
- Supports manual/motorized operation with reliable interlocks, simplifying switchgear design.
- Fully insulated design (SMC supports) with conical insulators and transparent shield, ideal for armored switchgear.
- Flexible installation (front/side mount), easy maintenance and fuse replacement.
- 1. Upper contact base of disconnector
- 2. Insulating support frame
- 3. Transparent glass shield
- 4. Metal frame
- 5. Conductive tube of disconnector
- 6. Lower contact base of disconnector
- 7. Vacuum interrupter
- 8. Lower outlet base of vacuum interrupter
- 9. Drive unit of vacuum load break switch
- 10. Fuse
- 11. Tripping unit
- 12. Earthing switch
- 13. Operation hole for earthing switch
- 14. Cabinet door lock pin
- 15. Manual trip button
- 16. Operation hole for charging & closing
Product Display
Technical Parameters
1. Main Electrical Technical Parameters
| Parameters | Unit | Model | ||
| FZN25-12D/T630 | FZRN25-12D/T200 | |||
| Rated Voltage | kV | 12 | 12 | |
| Rated Frequency | Hz | 50 | 50 | |
| Rated Current | A | 630 | 200 | |
| Rated Breaking Current | Active Load Current | A | 630 | |
| Closed-loop Current | A | 630 | ||
| No-load Transformer Capacity | kVA | 1600 | ||
| Cable Charging Current | A | 10 | ||
| Rated Transfer Current | A | 1700 | ||
| Rated Short-time Withstand Current (4s) | kA | 20(25) | ||
| Rated Peak Withstand Current | 50(63) | |||
| Rated Short-circuit Breaking Current | kA | 31.5 | ||
| Rated Short-circuit Making Current | kA | 50(63) | ||
| Rated Short-time (1min) Power Frequency Withstand Voltage | kV | 42/48 | ||
| Rated Lightning Impulse Withstand Voltage (Peak) | kV | 75/85 | ||
|
Notes:
1) The rated short-circuit duration for the earthing switch is 2 seconds. 2) The 1min power frequency withstand voltage across the interrupter break is 35kV. |
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2. Main Mechanical Characteristic Parameters
| Parameters | Unit | Value | Note |
| Vacuum interrupter contact gap | mm | 6+(1to 0) | |
| Vacuum interrupter contact stroke | mm | -2+(1 to 0) | Measured contact spring compression stroke |
| Disconnector break gap | mm | ≥130 | |
| Phase-to-phase center distance | mm | 210±1 | |
| 3-pole closing non-synchronism of vacuum interrupter | ms | ≤3 | |
| Allowable contact closing bounce time of vacuum interrupter | ms | ≤3 | |
| Average closing speed of vacuum interrupter | m/s | 0.6±0.2 | |
| Average opening speed of vacuum interrupter | m/s | 0.9±0.2 | |
| Conductive loop resistance per pole | μΩ | ≤180 | |
| Maximum operating torque for manual operation | Nm | ≤160 | |
| Mechanical life | times | 10000 |
3. Motor Technical Parameters
| Rated Voltage | Rated Output Power | Normal Operating Voltage Range |
| ≈220V | 70W | 85%–100% of rated voltage |
4. Shunt Trip Unit Parameters
| Rated Voltage | Normal Operating Voltage Range |
| DC 220V / DC 110V | 80%–120% of rated voltage |
For the current-limiting fuse in the load break switch-fuse combination unit, the rated current of the fuse link shall be selected according to the transformer capacity. The reference parameters for selection are as follows:
| Transformer Capacity (kVA) | 100 | 125 | 160 | 200 | 250 | 315 | 400 | 500 | 630 | 750/800 | 1000 | 1250 | 1600 | 2000 |
| Fuse Rated Current (A) | 10 | 12.5 | 16 | 20 | 25 | 31.5 | 40 | 50 | 63 | 80 | 100 | 125 | 160 | 200 |
Outline and Installation Dimension
Frequently Asked Questions (FAQ)
What is the FZN25-12 vacuum load break switch used for?
The FZN25-12 is an indoor AC high-voltage vacuum load break switch designed for 12kV distribution systems. It is used to switch load currents, provide visible disconnection, and optionally incorporate an earthing switch for safe maintenance operations in medium-voltage switchgear.
What is the rated voltage and current of the FZN25-12?
The FZN25-12 has a rated voltage of 12kV and a rated current of 630A (for the FZN25-12D/T630 model). The FZRN25-12D/T200 variant offers a rated current of 200A. The rated short-time withstand current is 20kA (4 seconds), with a peak withstand current of 50kA.
Does the FZN25-12 support motorized operation?
Yes. The FZN25-12 supports both manual and motorized operation. The motor operates at approximately 220V AC with a rated output power of 70W and a normal operating voltage range of 85%–100% of the rated voltage. The shunt trip unit operates at DC 220V or DC 110V.
What is the mechanical life of the FZN25-12?
The FZN25-12 is designed for a mechanical life of 10,000 operations. The side-mounted spring operating mechanism is specifically engineered to extend service life and ensure reliable performance over long-term use in demanding distribution environments.
How do I select the correct fuse rating for the switch-fuse combination?
The fuse rated current should be selected based on the transformer capacity. For example, a 100kVA transformer requires a 10A fuse, while a 1600kVA transformer requires a 160A fuse. Refer to the fuse selection table in the Technical Parameters section for full reference values from 100kVA to 2000kVA.
Is the FZN25-12 suitable for armored switchgear applications?
Yes. The FZN25-12 features a fully insulated design using SMC supports, conical insulators, and a transparent flame-retardant shield, making it ideal for armored (metal-clad) switchgear. It also supports flexible installation options (front or side mounting) for ease of integration and maintenance.