How Can Industrial Power Systems Reduce Overcurrent Risks? Fusible Flameproof Wire Wound Resistors Gain Attention

With the continued growth in demand for industrial automation, smart manufacturing, and high-reliability power supply equipment in Japan, equipment manufacturers are placing higher demands on the stability and safety of circuit protection components. Especially in industrial power supplies, inverters, automated control cabinets, and EV charging equipment, overcurrent, short circuits, and abnormal loads can damage critical electronic components and even affect the overall operational stability.

In the Japanese industrial equipment sector, fusible wire-wound resistors are widely used in:

• Industrial switching power supplies (SMPS)
• Industrial automation control systems
• Inverters and frequency converters
• EV charging equipment
• Power tool control modules
• Smart home appliance control circuits

These applications typically face the following challenges:

• Large starting current surges;
• Long-term continuous operation;
• Strict stability requirements at high temperatures;
• Fast interruption of fault current in case of circuit malfunctions;
• High requirements for the flame-retardant properties of components.

Therefore, an increasing number of equipment manufacturers are focusing on fusible wire-wound resistor solutions that combine overcurrent protection with load stabilization capabilities.

To address the protection needs of industrial power supplies and automation equipment, we have launched the FKN-S series of fusible flame-retardant wire-wound resistors.

This series features a wire-wound design that maintains stable resistance characteristics while providing fusing protection. When an abnormal overload occurs, the resistor quickly fuses according to its design characteristics, helping to protect downstream circuits and critical electronic components. Its 200ppm/°C temperature coefficient, 1000MΩ insulation resistance, and wide operating temperature range of -55°C to +155°C provide a reliable foundation for the long-term operation of industrial equipment. The 16x rated power fusing characteristic helps achieve predictable circuit protection under abnormal operating conditions.

After project testing and equipment verification, the customer reported that the product performance met expectations.

During long-term operational testing, the FKN-S series maintained stable resistance values; in simulated abnormal load tests, the fuse protection action met design requirements. Simultaneously, the flame-retardant coating structure meets the safety requirements of industrial equipment.

The customer particularly appreciated the following features:

• Combination of fuse protection and resistance functions;
• Stable operation under wide temperature environments;
• Miniaturized structure facilitates equipment layout;
• Good consistency in batch production;
• Suitable for industrial power supplies and automation equipment applications.

As the requirements for safety, reliability, and long-term stable operation of industrial electronic equipment in Japan continue to increase, fusible flame-retardant wire-wound resistors are becoming an important component of circuit protection design.

The FKN-S series fusible flame-retardant wire-wound resistors combine the stable load capacity of wire-wound resistors with the characteristics of fusible protection. They possess key parameters such as a temperature coefficient of 200ppm/°C, insulation resistance of 1000MΩ, operating temperature range of -55°C to +155°C, and a fusing capacity of 16 times the rated power. They can be widely used in industrial power supplies, inverters, automated control systems, and EV charging equipment.

For Japanese equipment manufacturers seeking fusible resistor manufacturers, flameproof resistor suppliers, wire wound resistor manufacturers, and industrial power resistor solutions, this product provides a noteworthy technological option for improving circuit protection reliability.