MITSUBISHI ELECTRIC CORPORATIONPUBLIC RELATIONS DIVISION
7-3, Marunouchi 2-chome, Chiyoda-ku, Tokyo, 100-8310 JapanFOR IMMEDIATE RELEASE

No. 3429

Customer Inquiries

Media Inquiries

Overseas Marketing Section, Marketing Division
Power Distribution Systems Center
Energy & Industrial Systems Group
Mitsubishi Electric Corporation

Public Relations Division

Haiden@yr.MitsubishiElectric.co.jp
www.MitsubishiElectric.com/bu/powersystems/prd.gnews@nk.MitsubishiElectric.co.jp
www.MitsubishiElectric.com/news/

Mitsubishi Electric Corporation

Mitsubishi Electric Reports on Improper Testingof 72/84kV Cubicle-type Gas-insulated Switchgear
TOKYO, August 17, 2021 – Mitsubishi Electric Corporation (TOKYO: 6503) announced today that internal
investigations being conducted by the company revealed on July 28 that several inspections of 72/84kV CGIS (cubicle-type gas-insulated switchgear) manufactured at its Power Distribution Systems Center inMarugame, Kagawa Prefecture was not entirely in accordance with customer-requested standards, which
required compliance with the Japan Electrotechnical Committee (JEC), the Japan Electrical Manufacturers’
Association (JEM), or the International Electrotechnical Commission (IEC). There were also cases whereimproper statements were included in the inspection reports when inspections were conducted differently thanwhat the standards required at the time.
Mitsubishi Electric halted shipments of the products in question as soon as the issues were discovered.
Currently, only those products for which inspections are confirmed to have been conducted properly are being
shipped. Electric utilities and other customers using the products in question are being notified of the situation.
Regarding the safety, functionality or performance of products that have been shipped, the company has
conducted tests during several stages of production such as, product development, mass production, andinstallation, and during each of these stages, there were no confirmation of any issues regarding the products.
The company is not aware of any accident or other incident attributable to this matter. Mitsubishi Electric will
be open to special inspections of the products as needed upon discussion with any customer.
An investigative committee consisting of external experts was established by Mitsubishi Electric on July 2 andthe committee is currently continuing its investigations. The cause of these issues and measures to prevent any
recurrence will be announced as soon as the committee issues its final report. Meanwhile, Mitsubishi Electric
will publicly announce any other serious matter, including improper testing of other products that is newly
uncovered through further investigations.

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At present, Mitsubishi Electric has determined that there is no need to revise its consolidated earnings forecast
for the current fiscal year. The company, which is working sincerely with customers and implementing
necessary preventive measures, will disclose any potential impact on consolidated earnings forecast that comesto light hereafter.
Products in Question
72/84kV Cubicle-type Gas-insulated Switchgear
Models: GX-70V, HG-VA, HG-VG and HG-VG-A
Total orders: 863 (4,529 panels) shipped between 1996 and 2021
Discrepancies Identified (as of August 17, 2021)
The following conducts during routine testing prior to shipping have been uncovered:1)

Lightning Impulse Test
The lighting impulse test specified by JEC was not conducted, but a “good” result was entered in the test
report.

2)

Power Frequency Voltage Test
The power frequency voltage test specified by JEC-, JEM- or IEC- was not conducted, but a “good” resultwas entered in the test report.

3)

Partial Discharge Test
The partial discharge test specified by JEC- or JEM was conducted using a different voltage-application
pattern.
###About Mitsubishi Electric Corporation
With 100 years of experience in providing reliable, high-quality products, Mitsubishi Electric Corporation(TOKYO: 6503) is a recognized world leader in the manufacture, marketing and sales of electrical andelectronic equipment used in information processing and communications, space development and satellite
communications, consumer electronics, industrial technology, energy, transportation and building equipment.
Mitsubishi Electric enriches society with technology in the spirit of its “Changes for the Better.” The company
recorded a revenue of 4,191.4 billion yen (U.S.$ 37.8 billion*) in the fiscal year ended March 31, 2021. For
more information, please visit www.MitsubishiElectric.com*U.S. dollar amounts are translated from yen at the rate of ¥111=U.S.$1, the approximate rate on the Tokyo
Foreign Exchange Market on March 31, 2021

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