Fuji Electric Review Vol.63-No.3, 2017



FUJI ELECTRIC REVIEW Vol.63-No.3 ,2017 Electric Distribution, Switching and Control Devices

Electric Distribution, Switching and Control Devices


One of the important roles of electric distribution, switching and control devices is to secure a safe, efficient and stable supply of electric energy, and in this respect, there has been increasing expectation for improved reliability and efficiency in these types of devices.
Fuji Electric has been meeting these expectations by continuously expanding and renewing its lineup of compact, energy saving and medium-voltage devices developed especially for electric distribution and power supply systems and other equipment configurations. As a result, we have enjoyed a strong reputation for supplying the market with timely products that meet customer needs. In this special issue, we will introduce the latest technologies and products for electric distribution, switching and control devices, which improve ease-of-use, while contributing to safer and more efficient power supply through the evolution of Fuji Electric’s switching and breaking technologies.

[Preface] Rediscovering the Significance of Publishing Fuji Electric Journal
YOSHIDA, Kiyoshi

Electric Distribution, Switching and Control Devices: Current Status and Future Outlook
SUZUKI, KenjiOKAMOTO, Yasumichi
Fuji Electric’s electric distribution, switching and control devices have been supporting the world’s industrial needs as core components widely used in electric equipment and machinery, and as such, we have been developing products that capture recent market demand and megatrends. Our switching equipment has been supporting the DC systems of electric vehicles and mega solar. At the same time, our control devices and low-voltage equipment have been contributing to a reduction in assembly and maintenance man-hours and reduced wiring. Our medium-voltage equipment has achieved miniaturization, while improving safety and ease-of-use. Furthermore, our power monitoring equipment delivers high flexibility and compatibility with IoT. Our core technologies have been an essential element in the development of new products. While taking advantage of those for our major products such as Japan’s leading short-circuit generators and advanced analysis equipment, we have been working vigorously to continue improving the technological capabilities of materials, simulations, evaluations and manufacturing.

Screwless Terminal Technology and Products that Contribute to Panel Manufacturing Labor Savings
MACHIDA, NoriyoshiHAMADA, Yoshinobu
Many electric distribution, switching and control devices are used in controlboards and switchboards. In recent years, the decrease in skilled workers has led to a greater demand for reduced wiring person-hours, as well as maintenance-free and skill-free equipment operation. In order to develop labor saving equipment that meets these needs,we carried out customer interviews and surveys and implemented prototyping with the goal of solving their problems. As a result, we have developed a screwless terminal technology that contributes to reducing wiring man-hours, while miniaturizing the size and improving the ease-of-use, reliability and maintainability of panels. Furthermore, we have also developed a new plug-in circuit-breaker that improves reliability and facilitates convenience in order to meet the growing popularity of labor saving plug-in circuit-breakers.

“EX Series” Electronic Earth Leakage Circuit-Breaker that Contributes to Development of Smart Societies
The development of smart societies requires power distribution facility to have high power supply reliability. Protective devices used in the facility are required to suppress unnecessary operation and indicate the conditions via measurement and communication functions. In order to meet these demands, we have developed the “EX Series” electronic earth leakage circuit-breaker. It utilizes various technologies including structural design technology for optimum placement of sensors and conductors, leakage detection technology based on a zero-phase current transformer and electronic circuit design technology that improves noise immunity. This electronic earth leakage circuit-breaker has the same external size as a molded-case circuit-breaker, reducing installation area by 30% when compared with setups that incorporate a leakage module. This can save the installation space of switchboards.

“CP30F Series” Circuit Protector for Improving Safety and Wiring Workability
EMURA, Takeshi
A circuit protector is a circuit-breaker that possesses both overcurrent protection and switch functions. Fuji Electric has developed the “CP30F Series” small circuit protector, which contributes to improving safety and wiring workability. It adopts a screw lift-up structure where its washer and terminal screw lift up when the terminal screw is loosened, and they are supported by its case and cover. It also utilizes an IP20 structure where the outside of the terminal screw is enclosed by the case and cover, ensuring that the fingertips of operators cannot touch the live part.This has made it possible to reduce the procedures required in wiring work from 6 steps to 2 steps, while also reducing the volume and footprint by 20%.

“AY22 Series” and “DY22 Series” Command Switches (Φ22) for Chinese and Asian Markets
TAKANO, YoshihiroINOUE, TatsuyukiYAMADA, Takashi
The diameter of the mounting holes of command switches comply with IEC standards: Φ16, Φ22 and Φ30. Command switches have been more greatly expanding in China and Asia than in the Japanese market, and Φ22 mounting holes are mainly used. Fuji Electric has offered “AY22 Series” and “DY22 Series” Φ22 command switches for the Chinese and Asian markets. These series adopt a modular structure that enables a high-grade appearance and flexible combinations. We have also developed transformerless LED lamps for illuminated products that have small sizes with low prices. The standard terminal structure of those are conforms to the IEC protective structure standard (IP2X) to improve safety.

IEC Standard Compliant Vacuum Circuit-Breaker (12 kV, 24 kV) for Southeast Asian Markets
OKAZAKI, TakayukiKIKUCHI, MasanoriTOKUNAGA, Yoshihide
As Southeast Asia continues to experience steady growth, the vacuum circuit-breakers (VCBs) for markets there are required to be compliant with IEC standards. We have recently expanded our line-up of products to include 12- kV and 24-kV IEC standard compliant products for Southeast Asian markets. As a feature supporting IEC standard compliance, the products come with a mechanism that enables operators to insert/draw out a VCB into/from the outside of the switchgear. The 12-kV VCB has achieved a compact and lightweight design while improving safety and functionality through features such as a grounded metal shutter that covers the main circuit to which high voltage is applied. The 24-kV VCB adopts a solid insulation design that has enabled miniaturization of about 40% in volume compared with previous products.

“F-MPC60G Series” Multifunctional Digital Relay Providing High Visibility and Operability
KUDO, Hideki
Fuji Electric has incorporated customer needs into the development of the “F-MPC60G Series” multifunctional digital relay for providing high visibility and operability. In addition to including previous functionality such as a duplicated circuit configuration and alarm output based on an accident diagnosis function, the relay ensures compatibility with the existing product shapes, as well as mounting and wiring methods. It comes equipped with operation and display functions with color LCD operation display having enhanced user interface, as well as accident waveform recording function for supporting recording and analysis work at the time of accident occurrence. It is also compliant with IEC standards to meet with specifications of overseas customers.

“F-MPC Web Unit” and “F-MPC ZEBLA” for Implementing Energy Management Systems
ENJO, YoshihiroTAKAHASHI, Hideo
There has been a growing demand for realizing energy savings and high-reliability power supply in power distribution systems. In order to meet these needs, we have developed the new “F-MPC Web Unit” and “F-MPC ZEBLA.” The F-MPC Web Unit centrally manages the power usage measurement data of switchboards measured by the F-MPC Series. The F-MPC ZEBLA comes with energy management functions that facilitate building energy consumption monitoring, while maintaining a comfortable indoor environment via automatic control. The F-MPC ZEBLA collects various energy data measured by the F-MPC Series via the F-MPC Web Unit to implement power demand forecasts and energy-saving control management.

“SVE135” Sealed High-Voltage Contactor Having High Overcurrent Withstand Capability
NAKA, YasuhiroSHIBA, YujiSAKURAI, Yuya
The spread of environmentally friendly vehicles mounted with large-capacity batteries has required that quick charging circuits be equipped with contactors capable of high overcurrent withstand capability during times of failure or accident. In response to this demand, Fuji Electric has developed the “SVE135” sealed high-voltage contactor as a unit that adopts a unique contact structure that contributes to improving the safety of environmentally friendly vehicles. This unique contact structure makes it possible to cancel out most of the electromagnetic repulsive force generated at the time of short-circuit current flow without increasing the contact pressure of the contact. As a result, this compact and lightweight unit has achieved a high overcurrent withstand capability of 20 kA, which is more than twice as high as the previous model.

Simulation Technology Supporting Development of Sealed High-Voltage Contactors
SAKATA, MasayoshiTAKEMOTO, Takanori
Fuji Electric has developed a sealed high-voltage contactor for automotive applications that has a high overcurrent withstand capability to deal with high-output and large-capacity batteries. The high-voltage contactor achieves high-capacity switching and breaking performance despite its compactness because its contacts are arranged inside a sealed capsule container filled with a gas of good breaking performance. By conducting analysis-driven development that effectively utilizes simulation technology for various types of analysis, such as electromagnetic field, heat conduction and thermal analysis, we were able to determine feasibility in advance and implement a design that improves product performance and reliability.

Materials Technologies Supporting Electric Distribution, Switching and Control Devices
HARA, EijiYOSHIZAWA, ToshiyukiOYAKE, Yoshiaki
Electric distribution, switching and control devices, used in various regions of the world, are required to conform to the RoHS Directive, which restricts the use of specific hazardous substances that are harmful to the body and the environment, as well as other standards such as IEC, UL and CCC. Fuji Electric completed its substitution of specified hazardous materials before the effective date of the RoHS Directive. We are working to develop an alternative material for phthalic ester, which will have its usage restricted starting in July 2021. Furthermore, we have developed insulating coating materials that are less susceptible to cracking and peeling even when used in the complex shapes and have combined materials with processing methods that improve productivity. This allowed our new products to be compact, save energy, and meet quality and performance requirements.

Evaluation Technologies Supporting Electric Distribution, Switching and Control Devices
HATA, JunichiroNOMURA, KojiSHOJI, Kazuki
Electric distribution, switching and control devices cover various specifications ranging from low voltage to high voltage and from small currents to large currents, and as such, various evaluations need to be made during the development process to ensure that high-quality products are offered that meet the needs of the market. Fuji Electric has been improving product reliability and development efficiency by making use of its Techno Lab, which was completed in December 2014, to carry out four types of evaluations, including evaluation of elemental technologies, evaluation of reliability, evaluation from the viewpoint of users and characteristic evaluation based on product standards. In addition, we are enhancing our evaluation testing facilities, and have received certification as Japan’s only customer-lab accredited testing laboratory for low-voltage products.

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