VTZ-12DM indoor single-phase permanent magnet vacuum circuit breaker(Tongzhong Electric's special model) is an indoor switchgear for rated voltage 12kV, AC 50/60Hz. It adopts a permanent magnet operating mechanism, single-phase control, and a vertical layout structure. It is suitable for special occasions in various industrial and mining enterprises and power grid equipment. It can be used for special occasions such as single-phase grounding faults and switching capacitor banks.

Product Specifications

Specification Sheet

NO. NAME UNIT DATA NAME UNIT DATA	Name	Unit	Data
1	Rated Voltage	kV	12
2	Rated Frequency	Hz	50/60
3	Rated current	A	1250
4	Rated power-frequency withstand voltage	kV	48(Common value) /42(Across the isolating Distance)
5	Rated lighting impulse withstand voltage	kV	85(Common value) /75(Across the isolating Distance)
6	Rated short-circuit breaking current	kA	31.5
7	Rated-short-circuit making current (peak)	kA	80
8	Rated withstand current (peak)	kA	80
9	Rated duration of short circuit	s	4
10	Operating cycles at rated short-circuit breaking current	Times	E2
11	Mechanical endurance	Times	10000
12	Standard Operating sequence	-	O-0.3s-CO-180s-CO
13	All0wable wearing thickness of contacts	mm	≤3

Mechanical characteristics Table2

NO.	Name	Unit	Data
1	Clearance between open contacts	mm	11±1
2	Over-travel	mm	3.5±0.5
3	Average closing speed	m/s	0.7±0.2
4	Average opening speed(average speed at 6mm of initial opening)	m/s	1.1±0.2
5	Rated added external contact final force	N	3100±200N(31.5kA)
6	Make time	ms	≤25
7	Breaking time	ms	≤10
8	Contact bouncing duration at closing operation	ms	≤2

Product Advantages

Performance of circuit breaker：

E2-C2-M2;

Stable and reliable:

Permanent magnet mechanism, single-phase design, independent control of phases A, B, and C;

High conductivity:

A rational conductive circuit design meets a temperature rise level of 1.1 times the rated current;

High adaptability:

Compact size and independent design make it suitable for a variety of applications.

product-800-533

Product Applications

Single-phase grounding circuit breaker;

Phase-switching and reactive power compensation site;

Power grid system protection site;

Special testing site

Product Outline Drawing

Secondary Wiring Diagram

The mechanism itself does not have a control unit, and the secondary wiring is as shown below:

The typical wiring diagram of the external permanent magnet controller is as follows:

why choose us

product-717-476

Our Mission and Vision

Since our founding, we have been driven by a mission to revolutionize power transmission and distribution systems. Our vision is to expand our international market share and establish our VTZ brand as a symbol of quality and innovation in the electrical industry. We are committed to becoming a global leader, known for our dedication to advancing technology, ensuring quality, and prioritizing customer satisfaction.

After-sales and Service

We are committed to providing exceptional after-sales support to our global customers. Our services include worldwide technical support and warranty coverage, such as online remote technical support, video training, and on-site installation guidance. During the warranty period, we respond quickly to equipment defaults, and provide repair or replacement services, with the option to extend warranties as needed. To ensure effective communication, we also offer multilingual support and provide a comprehensive feedback mechanism that allows us to track customer satisfaction and continuously improve our service quality.

Excellence in research and development

Innovation is at the core of our business. We have independently developed the VTZ Series Vacuum Circuit Breakers and continue to invest in research and development to meet the evolving needs of the electrical industry. Our R&D team consists of senior technical experts with decades of experience in the design and manufacture of high and low voltage electrical equipment. Their expertise, combined with our advanced facilities, allows us to stay ahead of industry trends and continually optimize our product offerings.

Advanced manufacturing and production

We operate one of the most advanced and standardized assembly line manufacturing facilities in the industry, equipped with the latest technology, enabling us to produce a wide range of high quality electrical products with precision and efficiency. Wecomply with GB 1984-2024 and GB/T11022-2020 standards to ensure the highest quality. Our commitment to excellence is reflected in the durability, reliability, and compatibility of our products.

Adapting to industry trends

Guided by our strategic development plan, we continuously adapt our products to align with the latest trends in smart grids, power system automation, and high altitude environments. Our leading high-current, high-voltage, and long-life products are designed to meet the rigorous demands of today's power systems, providing our customers with reliable, maintenance-free solutions that stand the test of time.

Honors And Certifications

product-620-877 product-880-1274