Heatsinks, Varistors, Thermal Protection

The category of heatsinks, varistors and thermal protection offers a wide range of products aimed for engineers from many areas of broadly understood industry, but also other entities working in this type of business.

Radiators
Radiators are used for carrying heat created in the power semiconductive device during the flow of the current to the environment. To achieve that, most often used structures are radiators cooled with air or water.

Our offer includes:

Air radiators
Radiator enclosures
Radiator blocks
Water radiators
Radiator equipment

Radiators - usage
For filling and eliminating possible imperfections of the connection surface between the cover of the cooled element and the surface of the radiator, special based on silicone thermal conductive greases are used. However, they shouldn't be used in excess - thicker layers reduce heat conduction. One of the important things to be aware of is the right tightness between the cover of the semiconductive device and the radiator. For air radiators it’s helpful to use a pressure power indicator, while for other types the screw should be retightened with a dynamometric wrench.

There’s often a need for electrically isolating the semiconductor from the radiator through a thin insulation plate. Thermal resistance is different for various materials of the plate. For mica plate 0,05 mm thick it’s approx. 1°C/W, for mica plate 0,4 to 0,06 mm thick, which is silver plated on both sides, it’s approx. 0,5° C/W, and for 3 mm thick aluminum plate with an aluminum oxide insulation approx. 0,3°C/W.

Thermal protection
We provide thermal bimetal protection and thermistor protection based on PTC thermistors. They are intended for protecting electric engine coils and transformers, devices and power electronic components, and heating devices. These protection measures are produced in the form of a patty for montage on coils and in the version with a metal enclosure with a bolt for screwing in into the engine’s corpus or radiator.

Varistors
E60 and E80 varistor series is intended mostly for industrial usage, providing perfect overvoltage protection in devices of traffic control, rail and tram traction, power devices, and devices for mining industry. The cover of varistors provides protection from vibrations, air pollution and humidity.