Shihen Technical Corporation

Shihen Technical Corporation (四変テック株式会社) is a Japanese electrical equipment manufacturer headquartered in Tadotsu, Kagawa Prefecture, on the island of Shikoku. The company traces its origins to 1946, when Shikoku Transformer Co., Ltd. (四国変圧器株式会社) was established as a joint venture between Shikoku Electric Power's predecessor Shikoku Haiden and Osaka Transformer (now Daihen Corporation). It began operations repairing pole-mounted transformers and grew into a full-line maker of power distribution and industrial electrical equipment. In 1988 the company changed its name from Shikoku Transformer to Shihen Technical Corporation. The company describes itself as Shikoku's only transformer manufacturer and has built roughly eight decades of history supplying power equipment. Its product portfolio spans transformers and reactors (oil-immersed, molded, dry-type, pole-mounted, and environmentally friendly vegetable-oil types), switchgears and control boards for power distribution up to 33 kV, switching power supplies for office equipment, industrial machinery, semiconductor manufacturing equipment and LED lighting, precision press dies, automated machinery and press working, and electric water heaters including EcoCute heat-pump water heaters. It also engages in renewable-energy power generation and sales. Shihen Technical operates from a domestic base in Kagawa Prefecture with sales offices in Tokyo, Kanto (Sagamihara), Kansai (Takatsuki) and Chugoku (Fukuyama), and has overseas subsidiaries in Thailand (Shihen Thailand, established 1995), Vietnam (Shihen Vietnam, established 2007, with a Hanoi branch added in 2020) and China (Shihen Precision Mold Trading (Dongguan) Co., Ltd., established 2013). In December 2023 the company became a consolidated subsidiary of Daihen Corporation, reconnecting with one of its original founding partners. Shihen Technical's corporate philosophy is expressed in the motto 'Creative Service' (創造奉仕), meaning to serve society through creation. Its stated mission is to contribute to a safe and comfortable society through technology and manufacturing, supporting stable daily life through the electrical infrastructure that is rarely seen but constantly relied upon.

Shihen Technical Corporation was founded in 1946 as Shikoku Transformer Co., Ltd. (四国変圧器株式会社). Its founding general meeting was held in August 1946 as a joint venture between Shikoku Haiden (now Shikoku Electric Power) and Osaka Transformer (now Daihen Corporation), with capital of 170,000 yen. Operations began in October 1946, and the first repaired transformer was shipped in December of that year. Standard transformer manufacturing started in September 1947. Through the 1950s and 1960s the company expanded its capital and product range. It began manufacturing distribution-line fault section devices in 1956, wound-core transformers in 1959, cubicle-type high-voltage receiving equipment in 1961, and fluorescent lamp ballasts in 1963. In 1966 it developed and began manufacturing large electric water heaters. The Seiki (precision) plant was completed in 1968, the Takase plant in 1969, and the switchgear plant in 1970. A large transformer plant followed in 1972, and in 1974 the company developed and began manufacturing DC stabilized power supplies. A dry-type transformer plant was completed in 1978. In the 1980s and 1990s the company continued to build out its facilities and sales network. It opened a Tokyo sales office in 1984 (now Tokyo office). In August 1988 it changed its name from Shikoku Transformer Co., Ltd. to Shihen Technical Corporation. An electric water heater plant was completed in 1990, followed by a new electronics plant and a new fluorescent ballast plant in 1991. In 1995 it established Shihen Thailand Co., Ltd. A standard transformer plant was completed in 1997, and the transformer division obtained ISO 9001 certification the same year. The switchgear, water heater and electronics divisions obtained ISO 9001 in 2001 and 2002, and the company obtained ISO 14001 in 2005. In the 2000s and 2010s the company expanded overseas and into new businesses. It established Shihen Vietnam in 2007 and obtained ISO 9001 for its precision division in 2010. In 2012 the water heater and precision divisions were relocated to the Takase plant. A Chugoku sales office opened in Fukuyama in 2013, and in the same year it established the overseas subsidiary Shihen Precision Mold Trading (Dongguan) Co., Ltd. in China. In 2015 it began power generation and sales using solar power systems, and in 2016 it invested in olive processing and sales company Sō no Dia. A Kanto sales office opened in Sagamihara in 2017, and the Kansai sales office opened in Amagasaki in 2019 (relocated to Takatsuki in 2022). In 2020 Shihen Vietnam established a Hanoi branch. In December 2023 Shihen Technical became a consolidated subsidiary of Daihen Corporation, reconnecting with one of its original founding partners. The company continues to operate as a manufacturer of transformers, switchgears, switching power supplies, precision dies and electric water heaters, with domestic offices in Kagawa, Tokyo, Kanagawa, Osaka and Hiroshima prefectures and overseas subsidiaries in Thailand, Vietnam and China.

• 2006

  Large die plant for precision division completed.

• 2005

  ISO 14001 certification obtained.

• 2002

  Electronics division obtains ISO 9001 certification.

• 2001

  Switchgear division obtains ISO 9001 certification.

• 2001

  Water heater division obtains ISO 9001 certification.

• 1997

  Standard transformer plant completed; transformer division obtains ISO 9001 certification.

• 1995

  Shihen Thailand Co., Ltd. established.

• 1991

  New electronics plant and new fluorescent ballast plant (Takase) completed.

• 1990

  Electric water heater plant completed.

• 1988

  Company name changed from Shikoku Transformer Co., Ltd. to Shihen Technical Corporation.

• 1984

  Tokyo sales office opened (now Tokyo office).

• 1978

  New dry-type transformer plant completed.

• 1974

  DC stabilized power supplies developed and manufacturing begins.

• 1972

  Large transformer plant completed.

• 1970

  Switchgear plant completed.

• 1969

  Takase plant completed.

• 1968

  Seiki (precision) plant completed.

• 1966

  Large electric water heaters developed and manufacturing begins.

• 1963

  Fluorescent lamp ballast manufacturing begins.

• 1961

  Cubicle-type high-voltage receiving equipment manufacturing begins.

• 1959

  Wound-core transformer manufacturing begins.

• 1956

  Manufacturing of distribution-line fault section devices begins.

• 1947

  Standard transformer manufacturing begins.

• 1946

  Shikoku Transformer Co., Ltd. established as a joint venture between Shikoku Haiden and Osaka Transformer; operations begin; first repaired transformer shipped.

Shikoku's only transformer manufacturer and a long-established supplier of power distribution and industrial electrical equipment, emphasizing stable supply, environmental responsiveness and social contribution.

• Transformers and reactors

  Oil-immersed, molded, dry-type, pole-mounted, vegetable-oil and top-runner transformers, plus various reactors for industrial and power distribution use.

• Switchgears and control boards

  Power distribution and control equipment for voltages up to 33 kV, including extra-high-voltage, high-voltage and low-voltage equipment, monitoring and control devices, and disaster-response equipment.

• Switching power supplies

  Power supplies for office equipment, industrial machinery, semiconductor manufacturing equipment, and indoor/outdoor LED lighting including deep-UV sterilization devices.

• Precision dies, automated machinery and press working

  High-precision, high-difficulty precision press dies, press working, press machines and automated machines, and die standard and custom parts.

• Electric water heaters (EcoCute)

  Electric water heaters and residential heat-pump water heaters (EcoCute) providing safe, clean and economical hot water.

1. 1四変テック株式会社 公式サイトshihen.co.jp
2. 2沿革 | 四変テック株式会社shihen.co.jp
3. 3企業情報 | 四変テック株式会社shihen.co.jp
4. 4製品情報 | 四変テック株式会社shihen.co.jp
5. 5Shihen Technical Corporation (Japan) - Wikidatawikidata.org