Fire department in Japan urges check old capacitors

TOKYO - The fire department in Japan is urging factories and restaurants to check power efficiency devices as their old deteriorated capacitors have a high risk of causing a fire especially in the hot summer.

Low-voltage phase advance capacitor devices are set in switchboards and other power apparatuses at factories and eateries to improve energy efficiency, and the number of fires caused by such devices increases in the summer. Three fires believed to have been caused by capacitors in Tokyo between June 25 and 28 were reported to have been caused by record-breaking temperatures this summer in many parts of Japan. Tokyo Fire Department officials say that people should be on higher alert than usual summers.

According to the Tokyo Fire Department, a small fire occurred at a store in the suburban Tokyo city of Tachikawa at around 8 a.m. on June 28. It is believed that the capacitor device that had been used for more than 50 years in the facility's kitchen overheated and ignited.

Between 2017 and 2021, over forty-nine of them were thought to have been caused by capacitors in the Tokyo Fire Department'sTokyo Fire Department's precinct, and 85.7% of them occurred between June and September. A majority of the capacitor devices had been in place for more than 40 years. In one of the fires which have burned down a workshop-cum- home in the capital's Taito Ward in August 2020, killing a resident in his 80 s, the cause was believed to have been a deteriorated capacitor device more than 60 years old. Such devices manufactured in or before 1975 have no safety functions.

Fire officials said that people tend not to notice anomalies because capacitors keep working even if they have degraded, but the risk of fire increases as air temperatures rise, causing the devices to heat up and damage the insulator in the capacitors. An industry organization says it is desirable to replace the devices every 10 years.

In June, officials at Senju Fire Station in Tokyo's Adachi Ward began to visit factories and other facilities in its precinct to check the devices. The risk of fire increases if a degraded device is constantly used, according to Takashi Miyamoto. We want people to check if they are still using old capacitors.