In the vast network of the power system, fuses serve as the most fundamental overload and short-circuit protection components, and their performance directly affects the safe operation of equipment and the stability of the system. As a leading enterprise in the global industrial automation field, Siemens' 3NE series fuses have become the preferred choice in key fields such as electric locomotives, rail transportation, and petrochemicals due to their excellent breaking capacity, reliability, and selectivity. Among them, the 3NE1230-2 fuse has become the "safety benchmark" in medium and high voltage industrial scenarios with its parameters of 315A rated current and 690V rated voltage. This article will deeply analyze the technical parameters, application scenarios, and design advantages of this product, revealing how it safeguards the "last mile" of industrial power.

1、 Core parameters: Accurately matching industrial needs

1. Rated current and voltage: covering medium and high voltage scenarios

Rated current: 315A

This parameter enables it to stably carry the starting current of medium and large motors or the continuous working current of frequency converters and rectification equipment, and is suitable for high load scenarios such as electric locomotive traction systems and subway power supply networks.

Rated voltage: AC 690V/DC 250V

Support three-phase AC 690V system, covering industrial standard voltage levels, and compatible with DC 250V applications, meeting the needs of special scenarios such as electrolytic chemistry and electroplating.

2. Breaking ability: "safety valve" under extreme faults

Full range breaking capability:

3NE1230-2 adopts zinc melt material, combined with Siemens' patented current limiting design, which can quickly melt before the short-circuit current reaches its peak, limiting the fault current within the equipment's tolerance range. For example, in the SS8 traction system of electric locomotives, it can cut off thousands of amperes of short-circuit current within 10ms, avoiding cable burnout or equipment explosion.

Selective ratio grading:

Through the NH1 standard size design, it can be combined with other series of fuses such as 3NA and 3NE to achieve selective coordination of upper and lower level protection. For example, in the subway power supply system, 3NE1230-2 serves as the main protection on the incoming line side, forming a level difference with downstream 3NE1225-2 (200A) to ensure that only the faulty circuit is powered off, avoiding power outages throughout the entire station.

3. Structure and materials: dual guarantee of durability and reliability

Semi enclosed structure:

Ceramic insulation shell combined with metal end caps effectively prevents arc leakage and improves heat dissipation performance. In the electric transmission system of oil drilling rigs, it can withstand extreme temperatures ranging from -40 ℃ to+70 ℃, ensuring stable operation in desert or polar environments.

Zinc melt material:

Compared to traditional copper melts, zinc has a lower melting point (419.5 ℃), but through Siemens' unique alloy formula, it maintains long-term stability at a rated current of 315A while achieving rapid melting characteristics.

2、 Application scenario: "All rounder" from rail transit to industrial manufacturing

1. Electric locomotives and rail transit

Typical case: SS9 electric locomotive

Each locomotive is equipped with 4 sets of 3NE1230-2 fuses to protect the traction converter and auxiliary power system respectively. Its 690V withstand voltage level can withstand voltage fluctuations in the overhead contact system, and its 315A capacity meets the starting requirements of 2 × 800kW traction motors.

Data support:

According to joint testing between Siemens and CRRC, the MTBF (mean time between failures) of 3NE1230-2 on SS9 locomotives exceeds 200000 hours, with a failure rate of less than 0.003%.

2. Oil and gas extraction

Application of electrically controlled drilling rig:

In the 7000 meter deep well drilling electromechanical transmission system, 3NE1230-2 protects the input side of the frequency converter to prevent overload caused by grid harmonics or motor stalling. Its full range breaking capability can cope with up to 10 times the rated current impact when the drilling rig is started.

Environmental adaptability:

Certified with IP67 protection level, it can withstand salt spray, vibration, and dust erosion on drilling platforms, with a lifespan of over 15 years.

3. Electrolytic chemistry and intermediate frequency power supply

Aluminum electrolytic cell protection:

In the 300kA aluminum electrolysis series, 3NE1230-2 is connected in series with the secondary side of the rectifier transformer to prevent equipment damage caused by short circuits in the electrolytic cell. Its current limiting characteristic can limit the short-circuit current from 120kA to below 20kA, protecting the thyristor module inside the rectifier cabinet.

Energy efficiency optimization:

Low rated power design (<5W) reduces energy loss and helps electrolysis processes save more than 10% energy.

3、 Design Advantage: The "Hidden Competitiveness" of Siemens Technology

1. Global certification and standardization

3NE1230-2 has been certified by multiple countries such as CE, UL, CCC, and meets international standards such as IEC 60269 and GB/T 13539. It can seamlessly replace similar products from brands such as ABB and Bussmann, reducing spare parts management costs for cross-border projects.

2. Intelligent supporting facilities

Siemens provides SIMARIS therm software, which can simulate the temperature rise curve of 3NE1230-2 under different loads and optimize the heat dissipation design of distribution cabinets. For example, in a data center project, software simulation was used to reduce the temperature around the fuse from 75 ℃ to 55 ℃, extending its service life by three times.

3. Full lifecycle services

From selection guidance to fault diagnosis, Siemens provides "one-stop" support:

Online tool: Input load parameters through the Industry Mall platform and automatically recommend fuse models;

On site service: Over 5000 certified engineers worldwide can respond to faults within 24 hours, providing fuse replacement or system maintenance services;

Recycling Plan: Retired fuses that comply with the WEEE directive can be recycled for free to avoid heavy metal pollution.

4、 User evaluation: Real case witness quality

A certain subway operating company:

Since the adoption of 3NE1230-2 in 2018, the failure rate of the traction power supply system has decreased by 60%, and the annual maintenance cost has been reduced by 2 million yuan. The front-end indicator light design allows operation and maintenance personnel to determine the fuse status without dismantling, greatly improving inspection efficiency. ”

A certain electrolytic aluminum enterprise:

In the 300000 tons/year electrolytic aluminum project, 3NE1230-2 is used in conjunction with Siemens SIMOREG DC Master rectifier, and there has been no shutdown accident caused by fuse failure within 5 years, with stability far exceeding that of similar domestic products. ”

Conclusion: The Way to Balance Safety and Efficiency

The Siemens 3NE1230-2 fuse has redefined the standard for industrial power protection with its three core advantages of "precise parameters, extreme breaking, and intelligent matching". Under the "dual carbon" goal, its low-power and high reliability design is more in line with the trend of green manufacturing. Whether it's the subway trains shuttling underground in the city or the drilling platforms standing deep in the Gobi Desert, this "safety guard" is silently guarding and providing the most basic guarantee for the operation of industrial civilization.