Sefuse SF139E Thermal Fuse – Precision Overheating Protection at 142°C

When it comes to electronic safety and precision, the Sefuse SF139E thermal fuse stands out as a reliable and indispensable component. Designed for high-performance thermal protection, the SF139E is engineered to interrupt electrical flow in devices that exceed a critical temperature threshold of 142°C. Whether you’re an electronics hobbyist, engineer, or OEM manufacturer, this thermal fuse delivers unmatched protection, ensuring the safety and longevity of your devices.

What is the Sefuse SF139E?

The Sefuse SF139E is a thermal cutoff device rated for 10A at 250V. It is part of the reputable SEFUSE series developed by NEC SCHOTT (now part of Nippon Seisen Co., Ltd.), a leader in thermal protection technology. This fuse is designed to act as a one-shot thermal protector, meaning it opens the circuit permanently when the ambient temperature reaches or exceeds 142°C, effectively preventing overheating, fire hazards, and equipment damage.

With compact construction and high sensitivity, the SF139E is widely used in various applications such as:

• Power supplies

• Electric heaters

• Home appliances

• Transformers

• Lighting ballasts

• Chargers and adapters

Why Choose the Sefuse SF139E?

Here are several compelling reasons why the Sefuse SF139E is a preferred choice for thermal protection:

1. Precise Thermal Cutoff at 142°C

The SF139E is factory-calibrated to operate at 142°C, ensuring that devices are shut off before reaching dangerous levels of heat. This temperature rating makes it ideal for a wide range of mid-to-high temperature applications where precision is crucial.

2. High Reliability

Built with bimetallic thermal link technology and housed in a high-durability casing, the SF139E offers consistent performance under varying thermal conditions. It is a trusted component for environments where electrical and thermal integrity are essential.

3. Compact and Easy to Install

The cylindrical body and axial leads make installation straightforward, whether through-hole mounting or inline configuration. Its small size also allows for easy integration into dense circuit boards or confined mechanical assemblies.

4. Compliant with Safety Standards

The Sefuse SF139E meets global safety and environmental standards including UL, CSA, and VDE certifications. It is RoHS compliant, ensuring it meets international guidelines for hazardous substance elimination in electronics.

Technical Specifications

These parameters make the Sefuse SF139E one of the most dependable options for consistent overheat protection in electronic systems.

Applications of the Sefuse SF139E

The versatility of the Sefuse SF139E allows it to be used across a broad range of products and industries. Here are a few practical applications:

• Power Adapters and Chargers

Protect power converters and adapters from thermal damage due to overloading, short circuits, or component failure.

• Household Appliances

Ensure safety in devices such as coffee makers, hair dryers, toasters, and irons where rapid heating can pose risks.

• Transformers and Ballasts

Prevent thermal runaway and internal short circuits in transformers and magnetic ballasts, particularly in lighting systems.

• Heating Equipment

Ideal for electric heaters, soldering equipment, and industrial heating elements where thermal cutoff is essential for user safety.

• Battery Packs and Inverters

Safeguard battery-operated systems, including backup power supplies and inverters, from critical overheating events.

How the SF139E Works

The Sefuse SF139E uses a thermal pellet mechanism inside its casing. When the temperature exceeds its rated value of 142°C, the pellet melts and causes the spring-loaded contact mechanism to open, breaking the electrical connection.

This process is irreversible—once activated, the fuse must be replaced. This ensures that overheated devices are not simply restarted without proper inspection or repair, adding an extra layer of safety.

Product Availability

You can purchase the Sefuse SF139E thermal fuse directly from our website at Nikkoe.com. We offer competitive prices, UK-based stock, and quick shipping across the UK and worldwide.

Product Highlights:

• Model: SF139E

• Brand: Sefuse

• Rated Temp: 142°C

• Current/Voltage: 10A / 250V

• Condition: New

• Unit: Sold per piece

We also provide bulk purchasing options for commercial clients and OEMs. Whether you need one or one thousand units, we’ve got you covered.

Why Buy from Nikkoe.com?

At Nikkoe, we understand the importance of sourcing high-quality, reliable components. That’s why we supply only authentic, tested thermal cutoffs like the Sefuse SF139E. Here's what you can expect when shopping with us:

• Genuine Components: We only stock parts from reputable manufacturers.

• Fast Dispatch: Orders placed before cut-off time are dispatched the same day.

• Expert Support: Got a question? Our knowledgeable team is here to help.

• Secure Payment: Shop confidently with encrypted checkout and multiple payment options.

Final Thoughts

The Sefuse SF139E is a critical component for anyone designing or repairing heat-sensitive electronic equipment. With its precise 142°C activation point, robust 10A/250V rating, and dependable construction, it ensures that your devices operate safely under all conditions.

Whether you’re a professional or a DIY enthusiast, investing in a reliable thermal fuse like the Sefuse SF139E is a smart choice. Don’t wait until overheating causes damage—protect your devices today.

Visit Nikkoe.com now to place your order for the Sefuse SF139E thermal fuse and enjoy fast, secure, and dependable service.