System JD Co., Ltd.

System JD Co., Ltd. (株式会社システム・ジェイディー) is a Japanese company headquartered in Fukuoka City, Fukuoka Prefecture, founded on 1 March 2002 by Hiroshi Date, who serves as Representative Director and President. The company's name carries a deliberate meaning: the "JD" stands for "Joint Development," reflecting the founder's intent to bridge universities and research institutes with corporate product development, commercializing cutting-edge research while nurturing talent for the future. Date's own background was in semiconductor manufacturing inspection, where he worked on detecting production defects and improving product reliability, followed by research work at a public research institution that connected academic researchers with industry problems. Although the company began with roots in semiconductor inspection, its business focus shifted from semiconductors to energy, while consistently keeping inspection technology as its core. Today System JD's main businesses are the manufacture and sale of solar cell array testers and photovoltaic (PV) power generation-related services. Its flagship product line is the SOKODES series of solar cell array testers, including the SOKODES GF20P launched in March 2016. The company also markets a ground-fault (leakage) detector, the 20G, launched in September 2015, and earlier products such as the SOKODES10P-1 (2012) and an embedded SOKODES (2013), both now discontinued. System JD positions itself around making the quality standards of clean energy "visible." On its website it states that by visualizing quality benchmarks for clean energy, it will contribute to energy conservation in Japan and around the world. Its technology detects disconnections and ground faults in solar cell arrays from the junction box, which the company describes as an industry first: detecting both panel-internal disconnections and connection-cable disconnections, as well as ground faults, from the junction box. Beyond product sales, System JD is active in industry associations and international cooperation. It has held leadership roles in Japanese PV inspection bodies, including a representative director position at the Solar Power Generation After-Maintenance Association (2013) and an executive director position at the Japan Solar Power Generation Inspection Technology Association (2019). It has also been involved in JICA's solar power plant technology course, providing PV maintenance lectures annually since 2012. In recent years the company has pursued overseas collaboration, signing agreements with Indonesia's BRIN and the Indonesian Solar Power Association (AESI), participating in a business partnership signing ceremony at Taiwan's ITRI, and receiving recognition in a University of Tokyo graduate-school PBL program. The company remains privately held and is based at the Fukuoka System LSI Research & Development Center in Fukuoka City.

System JD Co., Ltd. was established on 1 March 2002 in Fukuoka, Japan, by Hiroshi Date. Date had previously worked at a domestic semiconductor manufacturer, where he was involved in manufacturing inspection to detect production defects, repeatedly formulating on-site problems and developing systems to solve them, thereby contributing to improved reliability of semiconductor products. He later worked as a researcher at a public research institution, where he tackled problems brought by semiconductor-related engineers through joint research with university professors. Through that experience he recognized both the difficulty and the importance of connecting university research with corporate product development and bringing cutting-edge research into actual businesses and products. He founded System JD to make that connection his own business challenge. The company name's "JD" stands for "Joint Development," expressing the aim of linking educational and research institutions with companies to commercialize and put cutting-edge research to practical use, while also nurturing the people who will carry that work into the future. The company's business field shifted from semiconductors to energy, but it has consistently developed its business around inspection technology. In March 2012 it began selling the solar cell array tester SOKODES10P-1 (now discontinued). From 2012 onward it has been entrusted with PV maintenance lectures for JICA's solar power plant technology course, continuing every year. In April 2013 it began selling an embedded SOKODES (now discontinued), and in December 2013 it took the position of representative director of the Solar Power Generation After-Maintenance Association. In September 2015 it launched the ground-fault detector 20G (now discontinued). In March 2016 it began selling the solar cell array tester SOKODES GF20P. In May 2019 it took the position of executive director of the Japan Solar Power Generation Inspection Technology Association. On its website, System JD highlights what it describes as an industry first: detection of disconnections and ground faults in solar cell arrays. Specifically, it detects panel-internal disconnections and connection-cable disconnections from the junction box, and can detect ground faults from the junction box. The company's management philosophy states that by making the quality standards of clean energy "visible," it will contribute to energy conservation in Japan and the world. In the mid-2020s System JD expanded its international engagement. In January 2026 it received the top prize at the final presentation of a University of Tokyo graduate-school Project Based Learning program, in which it had participated since 2021 with a focus on Tsushima. In February 2026, with support from the Kyushu Environmental Energy Industry Promotion Organization (K-RIP), it signed a basic agreement (memorandum of understanding) with Indonesia's National Research and Innovation Agency (BRIN) concerning advanced maintenance management technology. In April 2026 it participated in a business partnership signing ceremony at Taiwan's Industrial Technology Research Institute (ITRI) for a new business collaboration related to solar power plant maintenance and inspection. In June 2026 it was selected for the Reiwa 8 IST Research & Development FS Program (Startup Study Group category) for electrical diagnostics for solar power plants. In August 2026, with support from the IJBNET Association and K-RIP, it signed a letter of intent (LOI) with the Indonesian Solar Power Association (AESI). The company remains privately held and headquartered at the Fukuoka System LSI Research & Development Center in Fukuoka City.

• System JD Co., Ltd. founded

• Began selling solar cell array tester SOKODES10P-1 (now discontinued)

• Began annual PV maintenance lecture commissions for JICA's solar power plant technology course

• Began selling embedded SOKODES (now discontinued)

• Assumed representative director position at the Solar Power Generation After-Maintenance Association

• Began selling ground-fault detector 20G (now discontinued)

• Began selling solar cell array tester SOKODES GF20P

• Assumed executive director position at the Japan Solar Power Generation Inspection Technology Association

• Won top prize at University of Tokyo graduate PBL final presentation

• Signed basic agreement with Indonesia's BRIN on advanced maintenance management technology

• Participated in business partnership signing ceremony at Taiwan's ITRI

• Selected for Reiwa 8 IST Research & Development FS Program (Startup Study Group category)

• Signed LOI with the Indonesian Solar Power Association (AESI)

Inspection-technology specialist making clean-energy quality standards visible; industry-first detection of solar array disconnections and ground faults from the junction box.

• SOKODES GF20P

• SOKODES10P-1

• Embedded SOKODES

• Ground-fault detector 20G

1. 1system-jd.co.jpsystem-jd.co.jp
2. 2会社概要 | system-jd.co.jpsystem-jd.co.jp
3. 3System JD Co., Ltd. (Japan) - Wikidatawikidata.org