Delivering electric control systems for public works projects
Main Image
Through high speed real time control technology, our circuit breakers achieve the optimum phase angle control in an “transformer excitation inrush currents suppression device.” This technology is patented domestically by our company, and we are in the process of applying or patents overseas. Working in software manufacturing, electrical equipment maintenance and construction services as well, as we have built up experience and confidence in these areas. We also handle inquiries from major corporations or foreign companies.


  • Excitation rush current suppression type transformer (Inrush-Limiter T1)

    Excitation rush current suppression type transformer (Inrush-Limiter T1)

    [Product description] This device eliminates all kinds of impairments resulting from magnetizing rush current phenomena which arise when powering up a receiving substation transformer, and has the following main features. ・Super control functionality. When a closing operation instruction is received from the circuit breaker, it automatically issues a control command which performs the closing operation at the optimal phase angle, minimizing magnetizing inrush currents. ・Compact size and excellent maintainability. With a size identical to an overcurrent relay unit, connecting input and output signals is simple, and regular maintenance is not required. ・Powerful fail-safe and history management functions. The main control area does not inhibit the operation of “close” and “cut off” functions, and convenient tool software makes for flawless history management. [Authorization/Certification] ISO9001 certifiaction (04/26/2002) [Intellectual property] Method and device for generating exciting rush current waveform of three-phase AC transformers (Patent #4275178), transformer excitation rush current suppresion control method and device (Patent #4562747), transformer excitation rush current suppression control method and device (Patent #5050254), excitation rush current suppression type transformer (Patent #5343118) [Major facilities and equipment] Electrical CAD system, imitation power supply test device, all kinds of software development environments, NC turret punch press, bending press, powder coating system







21,000,000 (JPY)








222-1, Hama, Nobeoka, Miyazaki, 882-0862


Equipment construction


3,110,000,000 (JPY)


Toshiyasu Kai   President






[Company strength]
From power stations where electricity is generated to all kinds of settings in people's daily lives and industry activity where electricity plays an important role, we provide systems optimally suited to customers' needs regarding design and production of electrical equipment, as well as electricity related construction, maintenance, and software engineering.

[Business description]
In addition to our transformer excitation inrush currents suppression device (Inrush-Limiter T1), inspection support systems (Insup), solar power generator remote supervision systems (POINT-SCAN) and other power controllers, software systems and other items which implement supervision and control technology, we also provide services such as construction and maintenance operations related to electricity, instrumentation, electrical power equipment.

Construction industry (electrical work), manufacturing industry

[Strength of products/technologies]
Our transformer irush current suppression equipment  (Inrush-Limiter T1) clarifies the mechanism which causes the outbreak of magnetizing inrush current, and maintains the ideal phase angle for the circuit breaker through the use of high speed real time control technology. We have acquired 4 domestic patents for this technology, and applications have been completed through PCT for patents in 3 foreign countries and 1 region. In the field of software products, our proprietary software systems are built on the developmental expertise we have cultivated through carrying out the design of software systems for consigned plant and manufacturing equipment management operations. In terms of maintenance and construction, we have built up a large body of experience and confidence through working with regional companies and public works projects since the company's founding.

[Representative's message]
 Since this company's founding in 1949, we have received a great deal of support from local businesses, and built up our technology and technical skill through carrying out the jobs they have requested from us. Also, our management concept is “Moving forward together with our district, aiming to become an eastern Kyushu core business that all of Japan can be proud of” and we have begun planning and sales of our own original products. Moving forward, we will continue working with our local customers, with the intention of working to elevate our technical skills, as well as product quality and safety, in order to provide our products and services to a wider area, including foreign countries.

[Company structure for market development/overseas expansion]
The business department supervisor who handles new customer transactions is determined through inquiry and discussion with the client. Technical consultations are handled by technical supervisors from the technology and engineering departments, and also visit customers directly as necessary to solve problems. New customers are handled separately depending on the field of business using group activity, and all operations such as information gathering and management are carried out with honest sincerity whether clients are based in Japan or overseas.

[Market share/Ranking]
transformer excitation inrush currents suppression device(the only one in Japan), maintenance and construction services (top class in our home area)

[Awards and media coverage]
 [Public Recognition] Kyushu Regional Development Bureau Land and Infrastructure Administration Service Commendation (2013) / Noguchi Sho – Shourei Sho / Miyazaki Bank Home Town Promotion Fund, Industrial Development Department “Development of transformer excitation inrush currents suppression device” (2011) [Media Publications] Contribution to the Denki Gakkai Journal B (electric power and energy department magazine) / Monthly Report No. 245 (10/2013) Miyazaki Bank Economics Research Center / Nikkan Kogyo Shimbun – introduction of new products: transformer excitation inrush currents suppression device, remote supervision system 

ISO9001 (certified in 2008); special and general construction industry certified; licensed by the Minister of Land, Infrastructure, and Transport

[Joint research and development]
Dohshisha University (magnetizing inrush current EMTP analysis), University of Miyazaki (small hydroelectric power generation)

[Factory (domestic)]
Head Offices   Factory (Miyazaki prefecture, Nobeoka city)

[Factory (overseas)]
Residence (Taiwan)

[Other sites]
 Branch Store (Miyazaki prefecture, Miyazaki city), Office (Miyazaki prefecture, Nichinan city), Business Office (Fukuoka prefecture)

[Transaction form]
Sales of in-house manufactured goods, taking orders for disc-type products, electrical and instrumentation equipment construction and maintenance contracts, industrial use supervisory control software development, solar power generation equipment construction and maintenance contracts, sales of industrial meters

[Transaction terms]
Depending on our company's conditions.

[Main Clients / Business History (domestic)]
Asahi Kasei Corporation; Kyushu Electric Power; Oji Paper; Toshiba Mitsubishi Electric Industrial Systems Corporation; Ministry of Land, Infrastructure, Transport, and Tourism; Miyazaki prefecture; Oita prefecture

[Main Clients / Business History (overseas)]

[Exhibition History/Information]
Monodzukuri Fair Small to Mid-Sized Organization Booth 2013 / 2nd International Wind Expo: Tokyo Big Site (Planned)