Asiatronix thermal cutoffs: reliable range of solutions for upper limit temperature protection


“Within Asiatronix products portfolio – the company explains –, you can find an accurate and reliable range of products to the need for upper limit temperature protection. The ultimate solution for your protection. Thermal cutoffs ensure the safe and reliable operation of a wide range of products in which they are incorporated, providing optimal safety solutions. There are different series of thermal cutoff (axial and radial type, and pellet type), resistor assemblies, thermoprotector with resistor, and fusing resistors, with different series developed to suit a wide range of application by Uchihashi, market leader since 1918”. Asiatronix offers a wide range of Uchihashi thermal cutoffs from stock in Europe.

Thermal cutoff

The most relevant advantages of Uchihashi thermal cutoff are:
• non resettable thermal cutoff which uses fusible alloy for its thermal element;
• extremely simple construction ensures reliability;
• hermetically sealed thermal element reduces deterioration with age;
• superior thermal sensistivity;
• insulating container;
• detecting current is 0.1A or less;
• regular or long lead length available.

• Available from 0.3 to 11A – AC 250V and DC 50V.
• From 1.4 mm to 3.3 mm.
Asiatronix offers specific series for Lithium-Ion Rechargeable Batteries, overheat protection of voltage dependent resistor, surge protection device, lighting surge protection.

• From 0.8 to 3 A (AC 250V).
• Case length from 4 to 11 mm.
• Specific series for flow soldering, screw fixing, etc…
Asiatronix also offers as Uchihashi, dedicated series with ceramic case for higher thermal sensitivity.

• From 10 to 15 A (AC 250V).
• Metal case and sense temperature material of organic compound pellet.
• Non return type.

The resistor assemblies developed by Uchihashi combine a cement resistor with a fusible alloy type thermal cutoff.
They guarantee overheat protection function, coil winding for greater ability to withstand inrush current, and extremely robust electrical insulation and voltage withstanding properties after it functioned.
• High reliable inrush current device for switching mode power supplies.
• Rated power: 1.0 – 5.0 W.
• No troubles with residual resistance or continuity.

Thermoprotectors with resistors are other elements that combine thermal link with resistance elements.
The thermoprotector opens the circuit in case of abnormal temperature and circuit breakdown in second protection circuit of Lithium-ion rechargeable battery.
• Series A5MC (for example) working at 12 A rated current.

Fusing resistors are used in higher current condition. These series accept high current and open the circuit quickly by receiving signal current.
It opens a circuit within 60 sec. at room temperature by low signal current, below 1.5A. Resistor portion is connected to fuse portion electrically and it can cut off both portions simultaneously. It can be installed easily by M5 fastening screw.
• Current: 75 A – 120 A.
• Up to 400 V DC.
• Series BZ05 (for example) up to 120 A rated current.
Asiatronix is the European office of Uchihashi Estec, which is into the manufacturing of thermal cutoffs since 1918. Since then, the company has been pursuing advanced special alloy processing techniques and applied technologies. For nearly a century, the company has been at the forefront in the development of the most advanced alloy technologies – including the successful commercialization of the world’s first small alloy thermal cutoffs – while helping improve product safety and reliability in the manufacturing industry.

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