Product Overview

The ZN12-12/40.5 indoor high-voltage AC vacuum circuit breaker is designed for 12~40.5kV three-phase AC 50Hz systems, adopting advanced German technology for reliable performance. Its simple structure, strong breaking capacity, and long service life ensure safe, explosion-free operation with minimal maintenance. This breaker is particularly suitable for power plants, substations, and transmission systems, providing robust control and protection in demanding applications.

With fully equipped operational features and compliance with GB1984-89 High-Voltage AC Circuit Breaker Standards, the ZN12 series is ideal for scenarios requiring frequent switching operations or handling major load interruptions. Its ease of maintenance and reliable design make it a trusted choice for modern high-voltage power systems.

Figure 1: ZN12-12kV Inclined Type,  Figure 2: ZN12-12kV Horizontal Type,   Figure 3: ZN12-40.5kV Inclined Type

Type designation of ZN12 AC Vacuum Circuit Breaker

Model Designation for ZN12 Vacuum Circuit Breaker

• Z: Vacuum circuit breaker.
• N: Indoor type.
• 12: Rated voltage (kV).
• □: Design sequence number.
• □: Rated current (A).
• □: Rated short-circuit breaking current (kA).

Environmental Conditions

• Altitude: ≤1000m.
• Ambient Temperature: -25°C to +40°C.
• Relative Humidity: Daily average: ≤95%. Monthly average: ≤90%.
• Earthquake Intensity: ≤8 degrees.
• Operating Environment: Free from inflammable, explosive, corrosive substances, and severe vibration.
• Special Requirements: For non-standard conditions, please contact our technical team for confirmation.

Product Features of ZN12-40.5 Series

• High breaking capacity with low current resistance and long electrical lifespan.
• Compact front-to-back layout for reliable operation and easy maintenance.
• Flexible installation options, including horizontal fixed type, inclined fixed type, and middle-set movable type.
• Integrated structure combining the actuator and breaker body for seamless performance.
• Versatile spring energy storage mechanism supporting AC/DC and manual operations.

Main Technical Parameters

Item	Unit	Model
		I	II	III	I	II
Rated Voltage	kV	12	12	12	40.5	40.5
Rated Current	A	1250	1600	2000	1600	2000
Rated Short-Circuit Breaking Current	kA	31.5	31.5	31.5	25	31.5
Dynamic Stability Current (50kA 3s)	kA	100	100	100	80	80
Rated Short-Circuit Making Current (Peak)	kA	100	100	100	80	80
Rated Short-Circuit Breaking Times	Times	50			20
Rated Operating Sequence		Open-0.3s-Close Open-180s-Close
Rated Insulation Level	kV	75			185
Power Frequency Withstand Voltage (1min)	kV	42			95
Closing Time	ms	≤75			50~85
Opening Time	ms	≤60 (50)			40~85
Mechanical Life	Times	10000			6000
Rated Current Breaking Times	Times	20000(11V) 10000(V~X)			20
Energy Storage Motor Power	W	275			275
Energy Storage Motor Rated Voltage	V	AC/DC110, 220			AC/DC220, 110
Energy Storage Time	S	≤15			≤15
Closing Electromagnetic Rated Voltage	V	110, 220			220, 110
Opening Electromagnetic Rated Voltage	V	110, 220			220, 110
Energy Storage Split Excitation Rated Voltage	V	110, 220			220, 110
Closing Interlocking Rated Voltage	V	110, 220			220, 110
Loss-of-Pressure Rated Voltage	V	110, 220			220, 110
Overcurrent Rated Excitation Current	A	5			5
Auxiliary Switch Rated Excitation Current	A	AC10 DC5			DC10
Contact Opening Distance	mm	11 ± 1			23 ± 2
Contact Overtravel	mm	8 ± 2			5 ± 1
Opening Speed	m/s	0.6~1.8			0.8~1.4
Closing Speed	m/s	1.0~1.8			1.1~1.8
Contact Closing Bounce Time	ms	≤2			≤3
Phase Center Distance	mm	210 ± 1.5 (280 ± 1.5)			350 ± 1.5 (460 ± 1.5)
Three-Phase Contact Closing/Opening Synchronism	mm	≤2			≤2
Each Phase Circuit Resistance	μΩ	≤35			≤45

Note: The closing speed refers to the average speed of the contact over the final 6mm, while the opening speed refers to the average speed of the contact during the first 6mm of separation.

Outline and Dimensions of Installation

Figure 1: ZN12-12 Inclined Type Outline Dimensions

Figure 2: ZN12-12 Horizontal Type Outline Dimensions

Figure 3: ZN12-40.5 Inclined Type Outline Dimensions

Special Customization Options

For non-standard configurations or specific project requirements, we offer customized solutions tailored to meet your needs. These may include:

• Special Operating Conditions: Adaptations for higher altitudes, extreme temperatures, or unique environmental challenges.
• Enhanced Performance: Custom short-circuit breaking currents or extended mechanical life.
• Control Integration: Specific control or monitoring interfaces for advanced systems.
• Specialized Mounting: Unique installation or mounting configurations.

For custom requirements or additional technical assistance, please contact our technical team. We are committed to delivering tailored solutions for your specific operational needs.

FAQs for ZN12 Indoor AC Vacuum Circuit Breaker

1. What applications is the ZN12-12/40.5 circuit breaker best suited for?
   The breaker is ideal for power plants, substations, transmission systems, and industrial facilities requiring frequent switching and reliable fault protection.
2. What are the insulation capabilities of the ZN12-12/40.5?
   It supports power frequency withstand voltages of up to 95kV and impulse voltages of 185kV, ensuring high reliability in demanding conditions.
3. What installation configurations are available?
   The breaker can be installed in horizontal fixed, inclined fixed, or middle-set movable configurations, offering flexibility for various system setups.
4. How does the ZN12-12/40.5 handle high-frequency switching operations?
   With a mechanical life of up to 10,000 operations, it is designed for frequent switching and heavy-duty applications.
5. Can the ZN12-12/40.5 be customized for specific needs?
   Yes, customization options include short-circuit breaking current adjustments, enhanced insulation, and control system integration. Contact the technical team for tailored solutions.
6. What environmental conditions can the ZN12-12/40.5 operate in?
   It operates reliably in altitudes up to 1000m, temperatures from -25°C to +40°C, and earthquake intensities up to 8 degrees. Special adaptations are available for extreme conditions.

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