Product Overview
The ZW32-12MG series is a three-phase AC 50Hz, 12kV outdoor vacuum circuit breaker for switching, making and breaking load, overload and short-circuit current in power systems. It suits frequent-operation duty in substations, industrial and mining distribution systems and rural grids. A permanent magnet operating mechanism provides the holding force, keeping contacts reliably open or closed without continuous power consumption; the reduced parts count and shortened transmission chain raise reliability and mechanical life. The integrated isolating switch (G) gives a visible break point for maintenance safety, and pairing the unit with a controller forms a recloser with remote signalling, measurement, control and protection for distribution automation.
Product Display
Model Designation
Model format: ZW32-12MG 630-20
- ZW: Outdoor Vacuum Circuit Breaker
- 32: Design Sequence Number
- 12: Rated Voltage (kV)
- M: Permanent Magnet Operating Mechanism
- G: With Isolating Switch (Disconnector)
- 630: Rated Current (A)
- 20: Rated Short-Circuit Breaking Current (kA)
Service Conditions
- Ambient temperature: -45 degC to +40 degC
- Altitude:
- Wind speed:
- Air pollution degree:
- Site free from fire, explosion, chemical corrosion and violent vibration
Construction
Each pole contains a vacuum interrupter enclosed in a solid dielectric epoxy resin bushing, driven by a direct-acting permanent magnet mechanism with minimal moving parts for high reliability and maintenance-free operation.
A three-phase ganged disconnector mounted above the breaker poles provides a visible air-gap break point, and a weatherproof base enclosure houses the magnet coil driver, overcurrent trip unit (5A, +/-10%), auxiliary switches and a multi-core connector for an external controller; the assembly is hot-dip galvanised and supports single-pole and double-pole (H-frame) mounting.
Technical Data
| Item | Unit | Value |
|---|---|---|
| Rated voltage | kV | 12 |
| Rated frequency | Hz | 50 |
| Rated current | A | 630 |
| Rated short-circuit breaking current | kA | 12.5 / 16 / 20 |
| Rated short-circuit making current (peak) | kA | 31.5 / 40 / 50 |
| Rated peak withstand current | kA | 31.5 / 40 / 50 |
| Rated short-time withstand current (4 s) | kA | 20 |
| Rated operating sequence | – | O-0.3s-CO-180s-CO |
| Closing time / opening time | ms | 25~50 / 15~50 |
| Rated short-circuit breaking times | ops | 30 |
| Mechanical life | ops | 10000 |
| Control & auxiliary circuit 1-min power-frequency withstand | V | 2000 |
| Rated operating voltage (control & auxiliary) | V | DC220 / AC220 |
| Overcurrent trip unit – rated current | A | 5 |
| Overcurrent trip unit – accuracy | % | +/-10 |
| 1 min power-frequency withstand (dry) | kV | 42 (to ground/phase), 48 (across open contact) |
| 1 min power-frequency withstand (wet) | kV | 34 (to ground/phase) |
| Lightning impulse withstand (peak) | kV | 75 (to ground/phase), 85 (across open contact) |
Standards
The ZW32-12MG is designed and type-tested to IEC 62271-100 and GB 1984 for high-voltage alternating-current circuit-breakers, covering insulation level, temperature rise, short-circuit making and breaking, and mechanical endurance.
Installation & Dimensions
Installation Diagram
The ZW32-12MG is designed for outdoor pole-mounted installation on either a single pole or a double-pole (H-frame) configuration, as shown in the outline drawing. The permanent magnet mechanism requires no spring charging motor, simplifying wiring to the controller. The integrated isolating switch is accessible from below for manual or electrically-operated ganged switching. Adequate clearance must be maintained around the unit, and all primary and secondary connections must comply with local utility standards.
| Dimension | Value (mm) |
|---|---|
| Total height | 760 |
| Total width (incl. bushings) | 990 |
| Base / frame width | 920 |
| Phase spacing (adjacent poles) | 340 |
| Overall depth (side view) | 790 |
| Mounting hole span (W x D) | 460 x 225 |
| Bushing flange width | 160 |
| Insulator mounting span | 360 |
| Pole-mounting bolt holes | 4 x 13 |