Fuji Electric FA Components & Systems Co., Ltd.

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  • Circuit breaker
  • Magnetic contactor, Magnetic starter

Changes of Molded case circuit breaker, Earth leakage circuit breaker

Which generation does your molded case circuit breaker belong to?

低圧配線用遮断器の変遷

Which generation does your earth leakage circuit breaker belong to?

低圧漏電遮断器の変遷

Recommendation of preventive maintenance

 

Renewing equipment at the appropriate time prevents serious accidents and their spread

Internal equipment used in receiving/distribution facilities has a limited life expectancy.

For your safe use of distribution facilities, the key is to operate them based on the operating environments recommended by the electrical manufacturer, periodic maintenance and inspection, and equipment upgrade at the appropriate time.
保守点検

 

Preventive maintenance is important

　Preventive maintenance is based on the idea that equipment is renewed or repaired before its life expectancy is reached when allowable failure rate values are exceeded. Preventive maintenance reduces failure rates (including power outages and accidents) significantly.
  1. Time based maintenance: planned replacement and repair before the failure rate exceeds its allowable value.
  2. Condition based maintenance: planned replacement and repair when the failure rate exceeds its allowable at periodic diagnosis.

(a) Early failure period: After a start of operation, there are possibilities of weaknesses that take time to adopt to an external environment and of failures in manufacture.
(b) Random failure period: The failure rate constantly continues without any relation to elapsed time.
(c) Wear-out failure period: The failure rate keeps increasing due to equipment deterioration or wear of components. This is the period witch you have to consider an overhaul or a upgrade of equipment for maintaining the functionality as a facility.

 

Recommended upgrade periods of equipment

The Japan Electrical Manufacturers' Association (JEMA) suggests the following recommended upgrade periods by type of equipment used for high-voltage facilities based on reports from the Institute of Electrical Engineers of Japan and questionnaires to business operators by the Ministry of Land, Infrastructure, Transport and Tourism.

Product Recommended upgrade period (after start of use)
Circuit breaker 15 years or specified switching times

 

 

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